A bus lane or bus only lane is a lane restricted to buses on certain days and times, and generally used to speed up public transport that would be otherwise held up by traffic congestion. Often restrictions do not apply to certain other vehicles, which may include taxis, high occupancy vehicles, motorcycles, and bicycles Bus lanes are a central part of bus rapid transit.
The first bus lanes in Europe were established in 1963 in the German city of Hamburg. Other large German cities soon followed, and the implementation of bus lanes was officially sanctioned in the German highway code in 1970. Many experts from other countries (Japan among the first) studied the German example and implemented similar solutions. On January 15, 1964 the first bus lane in France was designated along the quai du Louvre in Paris and the first counter-flow lane was established on the old pont de l’Alma on June 15, 1966. On 26 February 1968 the first bus lane in London was put into service on Vauxhall Bridge. By 1972 there were over 140 km of with-flow bus lanes in 100 cities within OECD member countries, and the network grew substantially in the following decades.
A bus lane is not necessarily very long, as it may only be used to bypass a single congestion point such as an intersection. Some cities have built large stretches of bus lanes amounting to a separate local road system, often called a busway system.
Entire roads can be designated as bus lanes (such as Oxford Street in London or Princes Street in Edinburgh), allowing buses, taxis and delivery vehicles only, or a contra-flow bus lane can allow buses to travel in the opposite direction to other vehicles.
Some bus lanes operate at certain times of the day only, usually during rush hour, allowing all vehicles to use the lane at other times, and it is common to have bus lanes in only one direction, such as for the main direction of the morning rush hour traffic, with the buses using normal lanes in the other direction.
Bus lanes may have separate sets of traffic signals, to allow priority at intersections.
Bus lanes may be marked in several ways. They must be demarcated by lines on the road; road signs may warn that they are bus lanes on certain days and times; descriptive text such as "BUS LANE" may be marked prominently on the road surface, particularly at the beginning and end; the road surface may have a distinctive colour. Other special-purpose lanes may similarly be marked, e.g. a cycle path may have bicycle symbols and a different coloured surface.
Evidence from the operation of urban arterials in Brisbane, Australia shows that a properly enforced Bus or Transit lane, operating as designed, can increase person throughput. In 2009 and 2010 traffic surveys showed that in Brisbane on a number of urban arterials with Bus and Transit lanes non-compliance rates were approaching 90 per cent. Following enhanced enforcement of the lanes, non-compliance rates dropped and overall efficiency of the Bus and Transit lanes improved with an up to 12 per cent increase in total person throughput in the lane. Average bus journeys times dropped, in some cases, by up to 19 per cent.
In London, UK, bus lanes may also be used by motorcycles, taxis and bicycles. Any other vehicles using bus lanes during the hours of operation will be fined £130 if caught by CCTV cameras installed specifically to monitor this kind of behaviour.
Bus lanes give priority to buses and cut down on journey times where roads are congested with other traffic.
The busiest bus lane in the United States is the Lincoln Tunnel XBL (exclusive bus lane) along the Lincoln Tunnel Approach and Helix in Hudson County, New Jersey which carries approximately 700 buses per hour during morning peak times an average of one bus every 5.1 seconds.
In contrast the Cross Habour Tunnel in Hong Kong carries 14,500 buses per day, or an average of about 605 an hour all day (not just peak times), but the bus lane must give-way to all the other road-users resulting in long queues of buses.
The introduction of bus lanes can significantly assist in the reduction of pollutants
Major networks 
Some network lengths of bus lanes in major cities, listed by buses per km of bus lane):
|City||Country||Population (million)||Buses (#s)||Population per bus||Bus lanes (km)||Buses per 1 km of bus lane|
|Kunming||People's Republic of China||5.7||~||~||42|
|Beijing||People's Republic of China||19.6||26000||754||294||88|
|Hong Kong||Hong Kong (PRC)||6.8||19,768 ||666||22||899|
|Country||Highway||Bus lanes (km)||Section|
|South Korea||Gyeongbu Expressway||137.4||Hannam IC (Seoul) ~ Sintanjin IC (Daejeon)|
|Hong Kong (PRC)||Tuen Mun Road||8.5||So Kwun Wat ~ Sham Tseng|
The installation of bus lanes requires additional space to either be constructed (increasing the impact of the road on the surrounding area, and possibly requiring private land) or taken from existing lanes; this may reduce the capacity of the road for private vehicles. The loss of lanes is controversial with many road users when this is actually an ancillary reason (i.e. when local authorities want to explicitly combine improved public transport options with reducing or at least not improving convenience for motorists).
thumb|Brt System in Delhi
Bus lane sign in Norway.
A bus lane in Church St, Parramatta, New South Wales
See also 
|Wikimedia Commons has media related to: Bus lanes|
- Bus priority
- Guided bus
- HOV Lane
- Public transport bus service
- Reversible lane
- Straddling bus
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