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Rydym yn croesawu galwadau’n Gymraeg. We welcome calls in Welsh.
Rydym yn croesawu galwadau’n Gymraeg. We welcome calls in Welsh.

The history of the road tunnels

There are 6 motorway and trunk road tunnels in Wales. They have enhanced connectivity and facilitated smoother transportation across various regions, contributing to economic development and tourism in the country.

Tunnels Timeline

Welsh tunnel map showing A55, M4 and A40 tunnels

A55 Conwy Tunnel

Built in 1991, this immersed tube tunnel was the first of its kind in the UK. At 1060m, the tunnel is the longest road tunnel in Wales.

A55 Penmaenbach Tunnel

Penmaenbach Tunnel opened in 1989 to carry westbound traffic. It is 658 metres in length and was blasted through the hillside.

A55 Penmaenbach Headland Tunnel

Built in 1932 Penmaenbach Headland tunnel was cut into the cliff by hand. It replaced the original coach road built by Telford in the early 19th century.

A55 Pen-y-Clip Tunnel

This tunnel was opened in 1994 after three-and-a-half years boring and shoring work that removed more than 103,000 cubic metres of granite from the headland.

M4 Brynglas Tunnel

The 360m twin bore, two lane holes, opened in 1967, are significant because they were the first tunnels to be built on the British motorway network.

A40 Gibraltar Tunnel

Built in 1969, these are a pair of bored tunnels, carrying the A40 through Gibraltar Hill.

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