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The Menai Suspension Bridge ( or ) is a
suspension bridge A suspension bridge is a type of bridge in which the deck (bridge), deck is hung below suspension wire rope, cables on vertical suspenders. The first modern examples of this type of bridge were built in the early 1800s. Simple suspension bridg ...
spanning the
Menai Strait The Menai Strait () is a strait which separates the island of Anglesey from Gwynedd, on the mainland of Wales. It is situated between Caernarfon Bay in the south-west and Conwy Bay in the north-east, which are both inlets of the Irish Sea. The s ...
between the island of
Anglesey Anglesey ( ; ) is an island off the north-west coast of Wales. It forms the bulk of the Principal areas of Wales, county known as the Isle of Anglesey, which also includes Holy Island, Anglesey, Holy Island () and some islets and Skerry, sker ...
and the mainland of
Wales Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic ...
. Designed by
Thomas Telford Thomas Telford (9 August 1757 – 2 September 1834) was a Scottish civil engineer. After establishing himself as an engineer of road and canal projects in Shropshire, he designed numerous infrastructure projects in his native Scotland, as well ...
and completed in 1826, it was the world's first major suspension bridge. The bridge still carries road traffic and is a Grade I listed structure.


Background

The Menai Strait was created by glacial erosion along a line of weakness associated with the Menai Strait fault system. During a series of
Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...
glaciation A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate be ...
s (that lasted from about 2,580,000 to 11,700 years ago), a succession of ice-sheets moved from northeast to southwest across
Anglesey Anglesey ( ; ) is an island off the north-west coast of Wales. It forms the bulk of the Principal areas of Wales, county known as the Isle of Anglesey, which also includes Holy Island, Anglesey, Holy Island () and some islets and Skerry, sker ...
and neighbouring
Gwynedd Gwynedd () is a county in the north-west of Wales. It borders Anglesey across the Menai Strait to the north, Conwy, Denbighshire, and Powys to the east, Ceredigion over the Dyfi estuary to the south, and the Irish Sea to the west. The ci ...
, scouring the underlying rock and creating a series of linear bedrock hollows. The deepest of these channels eventually became flooded by the sea as the ice sheets receded, forming the Menai Strait. As Anglesey has been an island throughout recorded human history, the only way to reach it was by crossing the strait. However, this has always been a dangerous endeavour because there are four strong tidal flows each day generated by the twice daily tides. These flow in both directions through the strait, creating strong currents and whirlpools. Despite the dangers, ferries operated all along the Menai Strait, carrying passengers and goods between the island and the mainland. In 1785, a boat carrying 55 people ran aground at the southern end of the Menai Strait in a strong gale and began to sink. The stricken vessel sank before a rescue boat from
Caernarfon Caernarfon (; ) is a List of place names with royal patronage in the United Kingdom, royal town, Community (Wales), community and port in Gwynedd, Wales. It has a population of 9,852 (with Caeathro). It lies along the A487 road, on the easter ...
could reach it, and only one person survived. Additionally, the main source of income on Anglesey was from the sale of cattle, and to move them to the markets of the mainland, including
London London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Wester ...
, they had to be driven into the water and encouraged to swim across the Strait. This often resulted in the loss of valuable animals. In 1800, Ireland joined Great Britain in the Act of Union. This led rapidly to an increase in people travelling between London and Holyhead en route to Dublin. In 1815, the
British Parliament The Parliament of the United Kingdom of Great Britain and Northern Ireland is the supreme legislative body of the United Kingdom, and may also legislate for the Crown Dependencies and the British Overseas Territories. It meets at the Palace of ...
passed an act of Parliament, the Holyhead Roads Act 1815 ( 55 Geo. 3. c. 152), to build the Holyhead Road with responsibility for the project given to civil engineer
Thomas Telford Thomas Telford (9 August 1757 – 2 September 1834) was a Scottish civil engineer. After establishing himself as an engineer of road and canal projects in Shropshire, he designed numerous infrastructure projects in his native Scotland, as well ...
. Despite some difficult geographical obstacles to overcome (e.g.
Snowdonia Snowdonia, or Eryri (), is a mountainous region and National parks of the United Kingdom, national park in North Wales. It contains all 15 mountains in Wales Welsh 3000s, over 3000 feet high, including the country's highest, Snowdon (), which i ...
and the Menai Strait), the route was chosen because Holyhead was the principal port for ferries to
Dublin Dublin is the capital and largest city of Republic of Ireland, Ireland. Situated on Dublin Bay at the mouth of the River Liffey, it is in the Provinces of Ireland, province of Leinster, and is bordered on the south by the Dublin Mountains, pa ...
as it was the closest point to Ireland. After Telford had completed a survey of the route from London to Holyhead, he proposed that the best option was to build a bridge over the Menai Strait from a point near Bangor on the mainland to the village of Porthaethwy (now commonly known as
Menai Bridge Menai Bridge (; usually referred to colloquially as ''Y Borth'') is a town and community on the Isle of Anglesey in north-west Wales. It overlooks the Menai Strait and lies by the Menai Suspension Bridge, built in 1826 by Thomas Telford, j ...
) on Anglesey. The site for the bridge was chosen because it had tall banks that would be high enough to allow
sailing ship A sailing ship is a sea-going vessel that uses sails mounted on Mast (sailing), masts to harness the power of wind and propel the vessel. There is a variety of sail plans that propel sailing ships, employing Square rig, square-rigged or Fore-an ...
s to pass underneath. Telford proposed that a suspension bridge would be the best option because it would have a span wide enough to cross the fast flowing waters of the Strait at this point. His recommendation was accepted by Parliament, which authorised the bridge in the Roads Between London and Holyhead Act 1819 ( 59 Geo. 3. c. 48).


Construction

Construction of the bridge, to Telford's design, 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 to support the span, each consisting of five parallel bars of
wrought iron Wrought iron is an iron alloy with a very low carbon content (less than 0.05%) in contrast to that of cast iron (2.1% to 4.5%), or 0.25 for low carbon "mild" steel. Wrought iron is manufactured by heating and melting high carbon cast iron in an ...
links, for a total of 80 iron bars and 935 links per cable. The chains were carried over the piers on
cast iron Cast iron is a class of iron–carbon alloys with a carbon content of more than 2% and silicon content around 1–3%. Its usefulness derives from its relatively low melting temperature. The alloying elements determine the form in which its car ...
saddles with rollers, allowing for movement caused by temperature changes. Each chain measured and weighed . Their suspending power was calculated at . To avoid rusting between manufacture and use, the iron was soaked in
linseed oil Linseed oil, also known as flaxseed oil or flax oil (in its edible form), is a colorless to yellowish oil obtained from the dried, ripened seeds of the flax plant (''Linum usitatissimum''). The oil is obtained by pressing, sometimes followed by ...
and later painted. On both sides of the strait the chains were conveyed through three tunnels into a chamber cut into the rock, where they were held in place by bolts resting in cast iron sockets. William Hazledine was contracted to supply the necessary wrought and cast iron, and each chain had four adjusting links to compensate for differences in length caused by imperfections during the production of the large number of separate links. Workmen assembled the majority of the chains link by link on-site. This was carried out on platforms near the tunnel mouths until the chains, supported by scaffolding, reached the tops of the piers. A cradle capable of carrying two workers was then suspended from each tower and links were lifted up and attached by the men in the cradles until the chains reached water level. The final central portion of each chain was floated across on a raft and lifted via a system of pulleys by 150 men. The bridge was opened to much fanfare on 30 January 1826. It reduced the 36-hour journey time from London to Holyhead by 9 hours.


Later history

The roadway was only 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-ton weight limit proved problematic for the increasing freight industry and in 1938 the original wrought iron chains were replaced by a new arrangement of
steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...
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, one carriageway of the bridge was closed for six months, restricting traffic to a single carriageway. The bridge was reopened to traffic in both directions on 11 December 2005 after its first major repainting in 65 years. It has been proposed by the British government as a candidate
World Heritage Site World Heritage Sites are landmarks and areas with legal protection under an treaty, international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural ...
. On 21 October 2022, the bridge was shut without prior notice. A statement from the Welsh Government said it was closed for essential maintenance work following safety recommendations from structural engineers. Initially, the bridge was shut completely in both directions, but it was soon reopened to foot passengers and dismounted cyclists. The Welsh Government stated the bridge would remain closed for 14 to 16 weeks, reopening in early 2023. On 1 February 2023, the bridge was reopened in both directions, but subject to a seven and a half ton weight restriction. A date for full remedial work has yet to be set.


Surroundings

The Anglesey Coastal Path passes below the bridge and the
Wales coast path The Wales Coast Path () is a designated long-distance trail which follows, or runs close to, the coastline of Wales. Launched in 2012, the footpath is long and was heralded as the first dedicated coast path in the world to cover the entire len ...
passes over the bridge and joins the mainland path at the bridge end. The bridge has a memorial to the Aberfan disaster victims on the Anglesey side.


Cultural references

The nearest settlement is the town of
Menai Bridge Menai Bridge (; usually referred to colloquially as ''Y Borth'') is a town and community on the Isle of Anglesey in north-west Wales. It overlooks the Menai Strait and lies by the Menai Suspension Bridge, built in 1826 by Thomas Telford, j ...
. 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.


Quotation


Famous Welsh


See also

* Britannia Bridge, second bridge over the Menai Strait, opened in 1850 * Menai Heritage Bridges Exhibition, museum about the Menai and Britannia bridges * List of bridges in Wales * Swellies * Operation Menai Bridge


References


Citations


Bibliography

* * Norrie, Charles Matthew (1956) ''Bridging the Years – a short history of British Civil Engineering'', Edward Arnold (Publishers) Ltd * *


External links


Menai Bridge Website
Menai Bridge Town Partnership Website with details on the news, council, events and businesses of Menai Bridge
Menai Heritage
A community project and museum celebrating the two bridges and the town of Menai Bridge * {{Authority control Bridges completed in 1826 Bridges in Anglesey Suspension bridges in Wales Bridges by Thomas Telford Landmarks in Wales Historic Civil Engineering Landmarks Road bridges in Wales Menai Strait Menai Bridge Bangor, Gwynedd Grade I listed buildings in Gwynedd Grade I listed buildings in Anglesey Grade I listed bridges in Wales 1826 establishments in Wales Bridges in Gwynedd Chain bridges