Menai Suspension Bridge
|This article needs additional citations for verification. (January 2012)|
Pont Grog y Borth
The Menai Suspension Bridge from a viewpoint on the A5 near the Britannia Bridge.
|Carries||A5 road (London to Holyhead)|
|Locale||Anglesey, North Wales|
|Total length||417 metres (1,368 ft)|
|Width||12 metres (39 ft)|
|Height||30 metres (98 ft)|
|Longest span||176 metres (577 ft)|
|Number of spans||Main: One
|Piers in water||Five|
|Design life||1893: wooden deck replaced in steel
1938/40: iron chains replaced in steel.
|Opened||30 January 1826|
|Heritage status||Grade 1
Candidate: World Heritage Site
The Menai Suspension Bridge (Welsh: Pont Grog y Borth) is a suspension bridge between the island of Anglesey and the mainland of Wales. Designed by Thomas Telford and completed in 1826, it was the first modern suspension bridge in the world.
Before the bridge was completed in 1826, the island had no fixed connection to the mainland and all movements to and from Anglesey were by ferry (or, with difficulty, on foot at low tide). The main source of income on Anglesey was from the sale of cattle, and to move them to the markets of the inland counties or London, they had to be driven into the water and swum across the Menai Straits. The Act of Union 1800 increased the need for transport to Ireland, and with Holyhead as one of the principal terminals to Dublin it was decided to build a bridge.
Thomas Telford was assigned the task of improving the route from London to Holyhead, and one of the key improvements was his design of the suspension bridge over the Menai Strait between a point near Bangor on the mainland and the village of Porthaethwy (which is now also known as Menai Bridge) on Anglesey. The design of the bridge had to allow for Royal Navy sailing ships 100 feet (30 m) tall to pass under the deck at high tide, and no scaffolding was allowed during construction as that would have violated the rule.
Construction of the bridge began in 1819 with the towers on either side of the strait. These were constructed from Penmon limestone and were hollow with internal cross-walls. Then came the sixteen huge chain cables, each made of 935 iron bars that support the 176-metre (577 ft) span. To avoid rusting between manufacture and use, the iron was soaked in linseed oil and later painted. The suspending power of the chains was calculated at 2,016 tons and the total weight of each chain was 121 tons. The bridge was opened to much fanfare on 30 January 1826 and reduced the journey time from London to Holyhead from 36 to 27 hours, a saving of 9 hours.
The roadway was only 24ft wide and, without stiffening trusses, soon proved highly unstable in the wind. The deck of the Menai Bridge was strengthened in 1840 by W. A. Provis and, in 1893, the entire wooden surface was replaced with a steel deck designed by Sir Benjamin Baker. Over the years, the 4.5 ton weight limit proved problematic for the increasing freight industry and in 1938 the original wrought iron chains were replaced with steel ones without the need to close the bridge. In 1999 the bridge was closed for around a month to resurface the road and strengthen the structure, requiring all traffic to cross via the nearby Britannia Bridge.
On 28 February 2005 the bridge was promoted to UNESCO as a candidate World Heritage Site. On the same day one carriageway of the bridge was closed for six months restricting traffic to a single carriageway so that traffic travelled to the mainland in the morning and to Anglesey in the afternoon. The bridge was re-opened to traffic in both directions on 11 December 2005 after its first major re-painting in 65 years.
The nearest settlement is the town of Menai Bridge. A representation of the Menai Bridge inside a border of railings and stanchions is featured on the reverse of British one pound coins minted in 2005. The coin was designed by Edwins Ellis.
- White Knight to Alice:
- "I heard him then, for I had just
- completed my design,
- To keep the Menai bridge from rust
- By boiling it in wine."
Famous Welsh englyn
- Uchelgaer uwch y weilgi - gyr y byd
- Ei gerbydau drosti,
- Chwithau, holl longau y lli,
- Ewch o dan ei chadwyni.
- —Dewi Wyn o Eifion (David Owen) (1784–1841)
- High fortress above the sea – the world drives
- Its carriages across it;
- And you, all you ships of the sea,
- Pass beneath its chains.
- Bartlett, W. H.; Harding, J.D.; Creswick, T. (Reprinted 2009). The Ports Harbours Watering Places. BiblioLife. ISBN 1-115-95868-2.
- Drewry, Charles Stewart (1832). A Memoir of Suspension Bridges: Comprising The History Of Their Origin And Progress. London: Longman, Rees, Orme, Brown, Green & Longman. pp. 46–66, and Plates. Retrieved 2009-06-13.
- Kovach, Warren (2010). "Menai Strait Bridges". Anglesey history. Retrieved 27 July 2010.
- The Saturday Magazine (Published by J. W. Parker): 212. 1835.
- Llwybr y Llewod 8-13. BBC Lleol
- Menai Bridge Website Menai Bridge Town Partnership Website with details on the news, council, events and businesses of Menai Bridge
- Prosiect Menai The new site of Prosiect Menai, who aim to create a museum and education centre based on the story of the bridges over the Menai Strait.