Motorway

Motorway symbol in Europe and some countries outside Europe.

A Sunday in April 2004 at 17:00 on the M25, which encircles London.

This article has a km/h to mph speed conversion table; speed limits are, therefore, quoted only in the units of measure of the country concerned.

A motorway is a dual-carriageway limited access highway with grade separated junctions designed and built solely for motorised traffic. The term is used in the United Kingdom, some parts of Australia, New Zealand, Pakistan, some other English-speaking Commonwealth nations, and Ireland.

Motorways are identical to freeways as a road type, and comparable to the United States's Interstate Highways as a classification; for all intents and purposes the nomenclatures are synonymous with each other.

Definitions

In Ireland, a road built to motorway standard but without the designation (and the regulations and traffic restrictions resulting from that designation) is known as a high-quality dual carriageway.

OECD Definition

The OECD has defined a motorway as:

French Equivalent: Autoroute.

Definition:

Road, specially designed and built for motor traffic, which does not serve properties bordering on it, and which:

(a) is provided, except at special points or temporarily, with separate carriageways for the two directions of traffic, separated from each other, either by a dividing strip not intended for traffic, or exceptionally by other means;

(b) does not cross at level with any road, railway or tramway track, or footpath;

(c) is specially sign-posted as a motorway and is reserved for specific categories of road motor vehicles.

Entry and exit lanes of motorways are included irrespectively of the location of the sign-posts. Urban motorways are also included.

Regulations and features

In Ireland, Hungary, parts of Australia and the UK, motorways are denoted by an 'M', prefixed (e.g. M1) or suffixed (e.g. A1(M)) road number and blue signage, distinguishing them from A‑roads or N‑roads, which are signed in green. This is at odds with some countries elsewhere in Europe, where the colours are reversed. In New Zealand, motorways are distinguished from regular state highways with the word 'Motorway' on entrance signage. New Zealand's motorways originally had green road signs while everywhere else had black. Now, the green signs were spread to the entire State Highway network (the national highways) by Transit New Zealand.

The construction and surfacing of motorways is generally of a higher standard than conventional roads, and maintenance is carried out more frequently; in particular, motorways drain water very quickly to reduce hydroplaning/aquaplaning. The road surface is generally asphalt concrete (popularly referred to as tarmac) or portland cement concrete. Other features are crash barriers, cat's eyes and, increasingly, textured road markings (a similar concept to rumble-strips).

Common criteria

This "motorway ahead" sign is used at each entrance to Irish motorways. The UK had similar signs before they were phased out, though old examples may still be found, and they are still used on some A(M)-class roads.

For a road to be classified as motorway the OECD conditions described above must apply. The implications of these conditions include:

• Accessed at junctions by slip roads off the sides of the main carriageway or joined by link-roads at an interchange, the object of which is to allow traffic to change route without stopping or slowing significantly;
• Traffic lights are seldom necessary except at toll booths and to control the number of vehicles entering the motorway from the slip road during busy periods) - see ramp meter;
• Certain types of transport are banned, typically pedestrians, bicycles, learner drivers, horses, agricultural vehicles, underpowered vehicles (e.g. small scooters, invalid carriages). In the Republic of Ireland, the "Motorway Ahead" sign at every motorway junction lists the excluded classes of vehicles (this sign was also formerly used in the United Kingdom - on which the Irish version is based - but has been almost entirely phased out). In the UK, at the last junction before a road becomes a motorway, a sign is posted, reading for "prohibited traffic". In most Australian states, a sign for "Motorway Entrance" or "Freeway Entrance" was put at the start of these roads, but these too are being phased out. In New Zealand, a no pedestrians and no motorcycles and no bicycles sign precedes the "Motorway Begins" sign.

The southbound M5 motorway near Bristol, showing typical British motorway signage including a driver location sign, a countdown marker and an overhead direction sign.

In the UK and in Ireland there are further restrictions:

• The central reservation with a continuous crash barrier (an exception being the Aston Expressway in Birmingham, which has an empty lane instead and a section of the M40 in Warwickshire, with an unusually wide grassy median strip separating the carriageways). Beginning in January 2005, and based primarily on safety grounds, the UK's Highways Agency's policy is that all new motorway schemes are to use high containment concrete step barriers in the central reserve. All existing motorways will introduce concrete barriers into the central reserve as part of ongoing upgrades and through replacement as and when these systems have reached the end of their useful life. This change-of-policy applies only to barriers in the central reserve of high speed roads and not to verge side barriers. Other routes will continue to use steel barriers. The Republic of Ireland has similarly introduced concrete barriers instead of its former policy of wide grass medians (the UK and Ireland share the same Design Manual for Roads and Bridges).
• Emergency telephones (which connect directly to the police, except in England, where they connect you directly to the nearest Highways Agency Regional Control Centre who will send either their own officers (HATO's) or other emergency services as required) are provided at a regular intervals (in the UK emergency telephones are situated at intervals of 1 mile, and at 2 km in Ireland)
• No roundabouts apart from at the start and finish (some exceptions)
• Hard shoulders are available most of the time.
• Other roads are connected at motorway interchanges only. No roads join at any other point except for maintenance access.
• Most junctions are numbered.

Note that these only apply to roads directly designated as motorways. Roads may also be indirectly designated as such: see Inheritance below.

Queues after a traffic collision on Britain's westbound M4

Traffic on a motorway is required to keep moving, except in exceptional circumstances (cases where traffic queues have built up, the vehicle has broken down, or the driver has been instructed to stop by a police officer). A minimum speed limit of 50 km/h applies in the Republic of Ireland.

A motorway in England and Wales, whether by design or inheritance, must have a Statutory Instrument (SI) defining a stretch of road and sliproads as a special road under the Highways Act 1980 (other legislation governs motorways with broadly similar effect in Scotland and Northern Ireland). In the Republic of Ireland, a Motorway Scheme must be made under the Roads Act 1993 prior to the road's construction. Alternatively, a Statutory Instrument defining the stretch of road as a motorway may also be made under the Roads Act 2007, but this process may be used only for high-quality dual carriageways open, in planning, or under construction on the day the Act was signed into law.

Speed limits

Speed conversion tables
km/h mph 50 31 60 37 70 43 80 50 90 56 100 62 110 68 120 75 130 81 140 87 150 93 mph km/h 30 48 40 64 50 80 60 97 70 113 80 129 90 145 100 161

Motorway safety is significantly higher than that of other roads, and the speed limits correspondingly higher, although some types of vehicle, such as heavy goods vehicles, may be subject to lower limits.

In the United Kingdom the speed limit for cars and motorcycles on motorways and dual-carriageways is 70 mph (plus an additional 60 MPH limit for goods vehicles, some buses, and cars/motorcycles towing a trailer, and even less for special vehicle classes) unless a lower limit is displayed; e.g. 50 MPH on the A38(M) and parts of the M4, staggered 70-50-30 MPH limits on approach to tolls, etc. Variable speed limit systems controlled with sensors, electronic signs (displaying as low as 20 MPH) and speed cameras are becoming more common to cope with increasing congestion and to improve safety. However, in most cases where sustaining 70 MPH may be generally unsafe - tight turns, etc - but still possible in a well-designed vehicle, the approach is instead to use passive signage displaying an advisory limit.

Many HGVs are restricted to 90 km/h (displayed as 56 mph) or 85 km/h (52/53 mph) because of EU regulations, and some large buses are limited to 100 km/h (62 MPH) similarly. British motorways originally had no speed limit, and were designed for traffic travelling up to 100 mph. Although the design speed of 100 mph remains, all British motorways and dual carriageways are now subject to the 70 mph National Speed Limit at best. A Department for Transport (DfT) study at several sites in 2006 showed that over half of all motorway traffic was travelling in excess of this limit. In 2004 the Conservative Party proposed increasing the motorway speed limit to 80 mph on some stretches, although this did not appear in their 2005 election manifesto. The Association of British Drivers supported the proposal, as they claimed it more closely represents the normal (and, they claim, safe) driving practice of the majority of motorway users. In March 2011 the Transport Secretary Philip Hammond announced a government review into the motorway maximum speed limit. He suggested the limit could rise to 80 mph to increase productivity and speed up the economy following the global recession.

Although there is no blanket lower speed limit imposed on British motorways, as some classes of vehicle permitted to use them (abnormal loads, construction vehicles) may be legally restricted to 40 MPH (64 km/h) or even as low as 18 MPH (30 km/h), and some sections present considerable gradients, most of the very slowest vehicles (mopeds, traction engines ("road locomotives"), and track-laying vehicles or anything else without pneumatic tyres and/or spring suspension) are prohibited. There is also an additional requirement for all vehicles - even those limited to 20 MPH or less - to be capable of sustaining at least 25 MPH (40 km/h) on level ground under normal load. Local minimum limits may also be set on sections where maintaining flow is a point of safety (e.g. long tunnels) as per any other road, and Police retain powers to take action against any driver travelling slow enough to cause danger or obstruction. This belies the inception of Motorways as bypasses simply allowing safe and uninterrupted - not necessarily high speed - travel, in an era where few common passenger cars could safely sustain a cruising speed of 60 MPH or more for very long and goods vehicles could struggle to exceed 40 MPH.

In Ireland the speed limit for motorways and some dual-carriageways is 120 km/h, up from 113 km/h (70 MPH) since metrification. In certain sections of motorway the speed limit is 100 km/h (also the default for dual carriageways without special authorisation); however, the vast majority of the network is 120 km/h.

In Pakistan, the speed limit on motorway was 140 km/h for light vehicles and 120 km/h for heavy vehicles; however, later it was restricted to 120 km/h for light vehicles and 110 km/h for heavy vehicles.

In New Zealand the speed limit on motorways and other dual carriageways is normally the top limit for state highways, 100 km/h, with restrictions in some areas, such as the Auckland Harbour Bridge and Central Motorway Junction (both have limits of 80 km/h).

In Australia the speed limit on motorways and other dual carriageways varies from state to state. In NSW, the state with the largest network of motorway standard roads, the limit is 110 km/h. Most other states observe a 110 km/h speed limit on some motorways, and the standard state limit of 100 km/h on others. Some roads, particularly in the Northern Territory, used to be completely unlimited, but are now under limits of 110-130 km/h (including the single-carriageway Stuart Highway as well as motorways).

In Turkey, the speed limit on motorways is 120 km/h.

In Germany, there is no general speed limit on a large proportion (approx 2/3rds) of its motorways (Autobahn); there are only particular speed limits (from 130 km/h on down) such as at dangerous sections, sections with traffic jam hazards, road works, or at some motorways through cities. There is an advisory speed limit of 130 km/h, above which insurers may reduce or refuse payouts in case of speed-related accidents, a legally enforceable minimum follow distance based on speed (1m per km/h), and a number of variable speed-limit systems which can show different signs from "unlimited" down to very low speeds (50 km/h or less) in response to bad weather, congestion, accidents etc.

In Poland, the speed limit on expressway was 130 km/h, but was increased on the end of 2010 to 140 km/h for cars and motorcycles. The limits for all other roads and vehicle classes remain unchanged.

In Italy, the speed limit on motorways generally is 130 km/h. It could be increased to 150 km/h by motorways owners only on 3+3 (or more) lane motorway with Safety Tutor device (a combination speed-warning and speed camera system; the limit can, theoretically, be applied on A1, A4 and A14 where this is installed). With rain, speed limit is 110 km/h, and 50 km/h in fog.

In Spain, the upper motorway and expressway limit is normally 120 km/h; as of Summer 2011, this has been "temporarily" reduced to 110 km/h to reduce the effects of a local oil crisis precipitated by the civil war in Libya.

In France and Luxembourg, the speed limit on motorways generally is 130 km/h;, however it is 110 km/h in rain or if there is water on the road, and 50 km/h in thick fog. Additionally, some sections (e.g. the Periphérique around Paris) may have reduced limits, as low as 70 km/h in places.

The lowest widespread speed limit on motorways in any country in Europe is Norway, where the limit usually is 100 km/h. The basic speed limit on all roads is 80 km/h, but most motorways have been given 100 km/h as a limit.

In Hong Kong, the speed limit is 70–100 km/h. Only one expressway, the North Lantau Expressway that connects the Chek Lap Kok International Airport, has a speed limit at 110 km/h.

In Romania, the speed limit on the A1 motorway is 130 km/h; however, this speed cannot be safely reached due to the degraded condition of the road (recommended speed is 100 km/h). On the A2 motorway (The Freeway of Sun), speed limits are 80 km/h during winter months and storms and 130 km/h for the rest of the year. Occasionally, fog occurs on the A2, making the traffic conditions become unsafe. The third section of the A2 is still under construction.

India has no car, truck or bus blanket speed limit on any of its roads other than local ones in towns, which extends to its fledgling motorway network. However, motorcycles are subject to a 50 km/h blanket limit.

Lanes

Diagram showing lanes and road layout, with Irish road markings.

Most motorway carriageways comprise a main running surface, with a hard shoulder along one edge, and a median or central reservation separating it from the other carriageway along the other edge. The hard shoulder is generally provided for use only in emergencies, such as breakdowns. However, parts of the M42 and M6 in the West Midlands (UK) have a system (Active Traffic Management) whereby a small section of the hard shoulder can be used as an extra lane during busy periods. This system is controlled with electronic signage also responsible for Variable Speed Limits and general lane closures/other warnings, as the section is under a lower limit during congestion-necessitated hard shoulder running (50 or 60 MPH dependent on location, vs 70 MPH usually), and any breakdown or accident in the hard shoulder area requires prompt re-closure of the lane to normal traffic. Sections where ATM is installed have "emergency refuges" provided every few hundred metres (resembling a small layby about long enough to hold a single articulated lorry, with an emergency phone) which are considered sufficient to deal with the occasional "soft" breakdown or punctured tyre experienced by more reliable modern vehicles. However, vehicles do still become stranded on the hard-shoulder running lane, either through misunderstanding or inability to reach a refuge.

The nearside edge (the edge up against the hard shoulder) of the running surface is marked with a solid white line, or in Ireland, a solid yellow line. The offside edge of the running surface (the edge nearest to the median) is marked with a solid white line. The running surface is divided into lanes by white dashed lines. In ATM sections in the UK, the hard shoulder line is not textured because it is frequently used as a running lane.

In the United Kingdom and in Ireland the lanes in a given direction are numbered sequentially from the nearside (hard shoulder), such as lane 1, lane 2, lane 3, etc.

The lane closest to the hard shoulder is generally intended for normal steady driving, while the other lane or lanes, those closer to the median, are intended for overtaking or passing slower-moving vehicles. Vehicles are expected to use the nearside-most lane that is clear, gravitating back towards the "nearside" lane even if already travelling at the speed limit. However, staying in lane to pass a moderately well-spaced line of significantly slower vehicles is permitted in preference to continually swerving between lanes. In concert with this, the British Highway Code states that vehicles must pass on the right, unless in heavy traffic or when the vehicle is turning left. Similar rules apply on German autobahns and in some other countries. In heavy traffic, it might be acceptable to cruise in any lane, and to pass slower vehicles on either side, to avoid continual lane changes.

Australia (traffic on left) is unique in that lane discipline is virtually unenforced. This results in overtaking on either side being routine and not punished. It is common for drivers to cruise in the right (fast) lane without yielding over to the slower lane to allow faster vehicles to pass.

Junctions

The N4/M50 interchange in Ireland, is a partially unrolled cloverleaf interchange

The most basic motorway junction is a two-lane flyover with four slip-roads, two on each side of the motorway, to exit or enter. A simple crossroads or roundabout is present at each end of the flyover. A rather large version of a roundabout, using two curved flyovers, is sometimes used to present a single large junction for users of the slip-roads or crossing road. The slip roads leading off the motorway are known as 'exit sliproads', those leading onto the motorway as 'entry sliproads'. The precise sliproad at any junction may be identified by reference to the direction of the carriageway, for example 'northbound entry slip'.

The signal-controlled roundabout is often used in these situations and has become very common in Ireland. A far greater degree of complexity is present in Britain, with varying types of Spaghetti Junction-style interchanges.The M50 Western Parkway in Dublin is going through a major upgrade with spaghetti style junctions being introduced to relieve traffic congestion.

Motorway junctions are usually given a number, indicated in the UK and in Ireland with a white number on a black background in the corner of signs approaching that junction. The same junction number is used in both directions on the motorway. Sometimes, where a junction is newly inserted between two existent junctions, it will be given a letter also (e.g. 2A). In Ireland, the junction numbering has been used consistently only on the M50 since it was opened, but a junction numbering scheme is now being applied to all motorways. This has necessitated certain junctions being renumbered on the M7 (and, in the future, on the M4). In Auckland, New Zealand, exit numbers are distance-based, and are indicated by a green sign reading "Exit XXX" (such as Exit 441) on top of exit signage.

In Ireland, when two motorways meet, it is often the end point/start point of one of the motorways. The motorway that is ending usually blends into the other at a restricted junction, permitting traffic to exit and enter the motorway from one direction only. Examples of this are the M4/M6 junction, the M7/M9 junction, and the under-construction M8/M7 junction. These junctions can cause frustration for road users, who must travel to the next available junction and then change direction to use the restricted exit.

Location and construction

Matrix warning sign as found on British motorways

Major intercity or national routes are often built or upgraded to motorway standard. Motorways are also commonly used for ring roads around cities or bypasses of built-up areas. In New Zealand, motorways tend to only occur in large cities, for purposes of taking commuters between the suburbs and the central city.

In Britain, there are plans to improve many motorways as well as to upgrade some roads to motorway status. In Ireland, the National Roads Authority has been connecting main cities with motorways as part of a six-year National Development Plan. The European Union has part-funded many motorway projects in the past, as part of a Trans-European Transport Networks, and there are plans to invest billions of euro in such projects in the next ten years, though this could be postponed due to the economic climate.

One of the most recently constructed motorways in the UK is the M6 Toll, bypassing Birmingham and Wolverhampton, which opened in December 2003 and is the only completely toll motorway in England. There are tolled sections of motorway on the M4 and M48, where they cross the River Severn at the Severn crossings. Although the crossing of the River Thames east of London on the M25 is tolled, the bridge and tunnels themselves are officially designated the A282 to permit usage by non-motorway traffic. In Ireland, the M1, M4, M8 and M50 all have tolled sections (the M50 toll being the only free flow toll in Ireland), and under construction sections of the M3, M6 and M7 also due to have tolls.

Intermediate forms

While a motorway is being built or upgraded, it may exist in an intermediate form sometimes referred to as semi-highway, half-motorway or semi-motorway that lacks all the characteristics of a finished motorway. Such a road is often a grade-separated, controlled-access undivided highway that constitutes a single carriageway of a future full-profile highway while the second one is built. While physically similar to two-lane freeways, these roads are strictly built as temporary structures as a part of a freeway or highway in construction.

Semi-highways can sometimes remain in the same state for long periods of time because of the high cost of building on certain terrain, such as in some parts of Switzerland. Sections of semi-highways are also frequently found in difficult terrain (where construction costs may be prohibitive), as a temporary and lower cost alternative to full construction. For example, instead of using two tunnel boring machines, one machine can excavate both without delaying the opening of the highway in either direction.

Most older motorways in Croatia were originally built in phases where the intermediate form existed, the most prominent example being the A6 motorway, large sections of which remained in this state between 2004 and 2008. The Croatian Roads Authority announced that in the five years ending in 2005 Template:Km to mi of highways were built and an estimated Template:Km to mi were being planned. In this same time frame Template:Km to mi of semi-highways were completed, with Template:Km to mi being planned.

Several sections of German Autobahnen have yet to be upgraded to full profile. The lower 100 km/h speed limit for undivided roads applies in derestricted speed zones, and passing may be permitted in the oncoming traffic lane. Examples include BAB 60 near the Belgian border and BAB 62 between Landstuhl and Pirmasens in Rhineland-Palatinate. In contrast, German federal highways (Bundesstraßen) are usually built as permanently undivided highways with frequent grade separations.

Newer Hungarian motorways are also built first as semi-highways and later completed. Examples are the M2 and M15. The M2 also features an unusual three-lane configuration. The M9 highway section connecting Szekszárd-Dombóvár in Transdanubia, Hungary will utilise 3 semi-highway sections during the construction process before achieving speedway status. Highway 66-611 will be modernized requiring a Template:Km to mi section to initially start with the construction of a two-lane semi-highway. The aim is to increase road security reducing collisions and achieve status similar to the M65 highway.

Swiss Autobahns are also sometimes built short of their design for topographical and financial reasons. The trans-Alpine A13 includes many tunnels and sections of semi-highway. These are similar to the Autostrassen, which are typically permanent structures.

Many toll roads in autopistas in Mexico are built in this way, often through difficult terrain.

The Pan-European Corridor X in Serbia will utilise semi-highways until full funding and construction can be completed. 800 million euros is the initial investment for construction of Corridor X, however it is estimated that another 1.6 billion euros will be needed for the entire length of construction. At this initial stage it is projected that about of Corridor X through Serbia will be finished highway, and the remainder of the route will be semi-highway or local main roads.

Inheritance

In the United Kingdom and in Ireland, certain types of traffic are not permitted on motorways. Thus, to avoid having people being forced to travel illegally, there are a number of rules about stretches of road that must be designated as motorways.

In all cases, there must be an escape route for traffic not wishing or not permitted to enter the motorway. As a result, the motorway technically begins as soon as the escape route has diverged from it. For example, at a grade-separated junction, the motorway starts at the junction with the exiting slip road, and the opposite slip road is also part of the motorway for this and the following reason. An exception was the A1(M) near Leeds, which was "illegal", since pedestrians could legally cross 300 yards beyond the start of the motorway, but then cyclists and other types of traffic not permitted on motorways had no way of turning back - the escape route was the "Boot and Shoe" one mile before. This is remedied by the A1(M) extension.

As a result, this creates a less-restrictive set of rules for the standard of the road. Roads whose only destination is a motorway must be assigned motorway status, notwithstanding the possibility of their not being built to normal motorway standards. For example, the A48(M) motorway outside Cardiff begins after the last exit to St Mellons, since by staying on the dual carriageway you cannot get anywhere other than the M4 eastbound; however, it is not a motorway-grade highway.

Route numbering

Great Britain

Main article: Great Britain road numbering scheme

In England and Wales, the numbers of major motorways followed a numbering system separate to that of the A-road network, though based on the same principle of zones. Running clockwise from the M1 the zones were defined for Zones 1 to 4 based on the proposed M2, M3 and M4 motorways. The M5 and M6 numbers were reserved for the other two planned long distance motorways. The Preston Bypass, the UK's first motorway, should have been numbered A6(M) under the scheme decided upon, but it was decided to keep the number M6 as had already been applied. Certain portions or bypasses of A-roads may be designated as motorways, the name of these portions being given the suffix "(M)". An example is the A1(M).

In Scotland, where the Scottish Office rather than the Ministry of Transport and Civil Aviation had the decision, there is no zonal pattern, but rather the A-road rule is strictly enforced. It was decided to reserve the numbers 7, 8 and 9 for Scotland. The M8 follows the route of the A8, and the M80 became part of the M90 when the A90 was re-routed along the path of the A85.

Northern Ireland

Signage on the M6 near Kinnegad in Ireland. This is the standard sign in Ireland and United Kingdom to indicate the start of motorway regulations - the appropriate motorway number is shown.

In Northern Ireland a distinct numbering system is used, which is separate from the rest of Ireland and from Britain, though the classification of roads along the lines of A, B, and C is universal throughout the UK and the Isle of Man. According to a written answer to a parliamentary question to the Northern Ireland Minister for Regional Development, there is no known reason as to how Northern Ireland's road numbering system was devised. However motorways, as in the rest of the UK and Ireland, are numbered M, with the two major motorways coming from Belfast being numbered M1 and M2. The M12 is a short spur of the M1 with the M22 being a short continuation (originally intended to be a spur) of the M2. There are two other motorways, the short M3 and a motorway section of the A8 road, known as the A8(M) (similar to how motorway sections of A-roads in Great Britain are numbered).

Republic of Ireland

In the Republic of Ireland, motorway and national road numbering is quite different to the UK convention. Since the passage of the Roads Act 1993, all motorways are part of, or form, national primary roads. These routes are numbered in series, (usually, radiating anti-clockwise from Dublin, starting with the N1/M1) using numbers from 1 to 33 (and, separately from the series, 50). Motorways use the number of the route of which they form part, with an M prefix rather than N for national road (or in theory, rather than R for regional road). In most cases, the motorway has been built as a bypass of a road previously forming the national road (e.g. the M7 bypassing roads previously forming the N7) - the bypassed roads are reclassified as regional roads, although updated signposting may not be provided for some time, and adherence to signage colour conventions is lax (regional roads have black-on-white directional signage, national routes use white-on-green).

Under the previous legislation, the Local Government (Roads and Motorways) Act 1974, motorways theoretically existed independently to national roads, however the short sections of motorway opened during this act, except for the M50, always took their number from the national road that they were bypassing. The older road was not downgraded at this point (indeed, regional roads were not legislated for at this stage). Older signage at certain junctions on the M7 and M11 can be seen reflecting this earlier scheme, where for example N11 and M11 can be seen coexisting.

The M50, an entirely new national road, is an exception to the normal inheritance process, as it does not replace a road previously carrying an N number. The M50 was nevertheless legislated in 1994 as the N50 route (it had only a short section of non-motorway section form the Junction 11 Tallaght to Junction 12 Firhouse until its extension as the Southern Cross Motorway). The M50's designation was chosen as a recognisable number. As of 2010, the N34 is the next unused national primary road designation. In theory, a motorway in Ireland could form part of a regional road.

Elsewhere

The A2 in Poland

In Hungary, similar to Ireland, motorway numbers can be derived from the original national highway numbers (1-7), with an M prefix attached, e.g. M7 is on the route of the old Highway 7 from Budapest towards Lake Balaton and Croatia. New motorways not following the original Budapest-centered radial highway system get numbers M8, M9, etc., or M0 in the case of the ring road around Budapest.

Also in the Netherlands, motorway numbers can be derived from the original national highway numbers, but with an A prefix attached, like A9 .

In New Zealand, as well as in the Scandinavian countries, and in Finland and Russia, motorway numbers are also derived from the state highway route that they form a part of, but unlike Hungary and Ireland, they are not distinguished from non motorway sections of the same state highway route. In the cases where a new motorway acts as a bypass of a state highway route, the original state highway is either stripped of that status or renumbered. A low road number means a road suitable for long distance driving.

In Australia, motorway numbering varies from state to state. Currently most states are adopting numbering systems with the prefix M for motorways.

In Pakistan, motorways are denoted with the prefix M.

Environmental effects

• Roadway noise: Motorways generate more roadway noise than arterial streets because of the higher operating speeds. Therefore, noise health effects are expected from motorway systems. Noise mitigation strategies exist to reduce sound levels at nearby sensitive receptors. The idea that motorway design could be influenced by acoustical engineering considerations first arose about 1973

History

Italy

See also: Autostrada and Autostrade of Italy

Italian Motorway A4 Turin - Trieste

The first motorway ever built in the world was the Autostrada dei laghi, inaugurated on 21 September 1924 in Milan. It linked Milan to Varese; it was then extended to Como, near the border with Switzerland, inaugurated on 28 June 1925. Piero Puricelli, the engineer who designed this new type of road, decided to cover the expenses by introducing a toll.

Other motorways built before World War II in Italy were Naples-Pompeii, Padua-Venice, Milan-Turin, Milan-Bergamo-Brescia and Rome-Ostia.

Germany

Main articles: German Autobahnen and AVUS

German Motorway (Reichsautobahn) 1943

Great Britain

See also: Roads in Great Britain

A map 'Shewing Future Pattern of Principal National Routes' was issued by the Ministry of War Transport in 1946 shortly before the law that allowed roads to be restricted to specified classes of vehicle (the Special Roads Act 1949) was passed. The first section of motorway, the M6 Preston Bypass, opened in 1958 followed by the first major section of motorway (the M1 between Crick and Berrygrove), which opened in 1959. From then onwards, motorways opened on a regular basis right into the 1980s; by 1972 the first 1,000 miles (1,609 km) of motorway had been built.

Whilst roads outside of urban areas continued to be built throughout the 1970s, opposition to urban routes became more pronounced. Most notably, plans by the Greater London Council for a series of ringways were cancelled following extensive road protests and a rise in costs. The completed M25 London Orbital opened in 1986. In 1996 the total length of motorways reached 2,000 miles (3,219 km).

Ireland

Legal authority existed in the Special Roads Act (Northern Ireland) 1963 similar to that in the 1949 Act. The first motorway to open was the M1 motorway, though it did so under temporary powers until the Special Roads Act had been passed. Work on the motorways continued until the 1970s when the oil crisis and The Troubles both intervened causing the abandonment of many schemes.

M9 Carlow Bypass under construction March 2008, which opened in mid 2008; the continuous yellow lines indicate a motorway rather than HQDC.

In the Republic of Ireland the Local Government (Roads and Motorways) Act 1974 made motorways possible, although the first section, the M7 Naas Bypass, did not open until 1983. The first section of the M50 opened in 1990, a part of which was Ireland's first toll motorway, the West-Link. However it would be the 1990s before substantial sections of motorway were opened in Ireland, with the first completed motorway – the 83 km (52 mi) M1 motorway – being finished in 2005.

Under the Transport 21 infrastructural plan, motorways or high quality dual carriageways are being built between Dublin and the major cities of Cork, Galway, Limerick and Waterford by the end of 2010. Other shorter sections of motorway either have been or will be built on some other main routes. In 2007 legislation (the Roads Bill 2007) was proposed to allow existing roads be designated motorways by order because legislation allows for only newly-built roads to be designated motorways.

It is now intended that all the HQDCs on the major inter-urbans (other than some sections near Dublin on the N4 and N7, which do not fully meet motorway standards) will be reclassified as motorways. The first stage in this process occurred when all the HQDC schemes open or under construction on the N7 and N8, and between Kinnegad and Athlone on the N6 and Kilcullen and south of Carlow on the N9, were reclassified motorway on 24 September 2008. Further sections of dual carriageway are proposed to be reclassified as motorway.

Australia

Most of Australia's capital cities feature a motorway network within their urban areas. Sydney, Melbourne, Brisbane and Perth each feature freeway and motorway systems, while Canberra, Adelaide, Hobart and the regional centres of Newcastle, Geelong, Gold Coast, and Wollongong feature a selection of limited-access routes. Outside these areas traffic volumes do not generally demand motorway-standard access, although heavily-trafficked regional corridors such as Sydney-Newcastle (M1 Sydney-Newcastle Freeway), Brisbane-Gold Coast (M1 Pacific Motorway) and Melbourne-Geelong (M1 Princes Freeway) that form part of major long-distance routes feature high-standard motorway links.

While Sydney and Canberra (NH23 Federal Highway (Australia)) are the only two Australian capitals connected by a continuous motorway-standard link, upgrades to full dual-highway of the heavy-use Sydney-Melbourne (A31/M31 Hume Highway/Freeway) and Sydney-Brisbane (M1 Pacific Highway) interstate routes, a total length of more than 2000 kilometres (1243 mi), are underway.

Unlike many other countries, Australia's motorways are being opened to cyclists. As the respective state governments upgrade their state's motorways bicycle lanes are being added and/or shoulders widened alongside the motorways.

New Zealand

Looking north over the Auckland Southern Motorway at the Princes Street interchange, near Otahuhu in Auckland City.

Most of New Zealand's major centres feature a motorway network within their urban areas. Auckland, Christchurch, Wellington and Dunedin each feature freeway and motorway systems, with most of New Zealand's major regional centres featuring a selection of limited-access or expressway routes. Outside these areas traffic volumes do not generally demand motorway-standard access. New Zealand's first motorway opened in December 1950 near Wellington. This 5 km (3 mi) motorway now forms part of the Johnsonville-Porirua Motorway and State Highway 1. Auckland's first stretch of motorway was opened in 1953 between Ellerslie and Mount Wellington (between present-day Exit 435 and Exit 438), and now forms part of the Southern Motorway.

Pakistan

File:M2 lilla.JPG

South Asia's first motorway: the 6-lane M2 motorway from Islamabad to Lahore in Pakistan

Main article: Motorways of Pakistan

Pakistan has a network of high-quality, international-standard limited access (or access-controlled) motorways, which are maintained and operated by the National Highway Authority. In August 2009, operational motorways in Pakistan had a combined length of 632 km (393 mi) with another 233 km (145 mi) under construction and further planned.

Pakistan's motorways are part of Pakistan's National Trade Corridor project that aims to link Pakistan's three Arabian Sea ports of Karachi, Port Qasim and Gwadar to the rest of the country and further on with Afghanistan, Central Asia and China.

Pakistan's first motorway, the M2, was inaugurated in November 1997 and was the first motorway to be built in South Asia. The M2 is a 367 km (228 mi) long, six-lane motorway that links Pakistan's federal capital, Islamabad, with Punjab's provincial capital, Lahore. Since the completion of the M2, two additional motorways have become operational. These are the 54 km (34 mi) 4-lane (with capacity to increase to 6 Lanes) M3 (Pindi Bhattian-Faisalabad), which links the M2 to Faisalabad and the 154 km (96 mi) 6-lane M1 (Peshawar-Islamabad). One additional motorway is currently under-construction, the 233 km (145 mi) 4-lane (with capacity to increase to 6 Lanes) M4 (Faisalabad-Multan).

Thailand

Main article: Thai motorway network

File:Motorway Chonburi.jpg

Motorway from Bangkok to Chonburi in Thailand

The Thai motorway network is an intercity motorway network that spans 145 kilometers (90 mi). It is to be extended to over 4000 kilometers (2485 mi) according to the master plan.

Thailand's motorway network is considered to be separate from Thailand's expressway network, which is the system of usually elevated expressways within Greater Bangkok. Thailand also has a provincial highway network.

The Thai highway network spans over 70,000 kilometers (43,500 mi) across all regions of Thailand. These highways, however, are often dual carriageways with frequent u-turn lanes and intersections slowing down traffic. Coupled with the increase in the number of vehicles and the demand for a limited-access motorway, the Thai Government issued a Cabinet resolution in 1997 detailing the motorway construction master plan. Some upgraded sections of highway are being turned into a "motorway", while other motorways are being purpose-built.

See also

• Highway
• Carriageway
• Motorway service area
• Rest area
• List of OECD countries by road network size
• List of highway systems with full control of access and no cross traffic
• Megaproject

List of motorways in

• Belgium
• Croatia
• Czech Republic
• Finland
• France
• Germany
• Hungary
• Ireland
• Italy
• Morocco
• The Netherlands
• New Zealand
• Pakistan
• Poland
• Slovakia
• Spain
• The United Kingdom

External links

• Department for Transport (United Kingdom)
• Highways Agency (England)
• Swiss Motorways (Switzerland)
• National Roads Authority (Ireland)
• eFlow - barrier free tolling operators on the M50 (Ireland)
• European Union Transport Policy
• CBRD Motorway Database
• SABRE Roads Portal
• Pathetic Motorways: Motorway Numbering Scheme
• How Motorways Work (satirical insight)
• Independent Auckland Motorways Website (New Zealand)
• Motorways in the Benelux (Benelux)
• Motorways in the Netherlands (The Netherlands)