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Cof Cymru: National Historic Assets of Wales · Wales

Portal at west end of Llandygai Tunnel

Llandygai, Gwynedd, Wales

A Grade II listed building in Llandygai, Gwynedd, designated on 24 May 2000.

Ordnance Survey six-inch map, 2nd edition (1888–1913) covering the location of Portal at west end of Llandygai Tunnel, Gwynedd, with a pin at the register's coordinates
Ordnance Survey six-inch map, 2nd edition (1888–1913), covering this location. Courtesy of the National Library of Scotland. The pin is ours, placed from the register's coordinates.

The record

Designation
Listed building, Grade II
Broad class
Transport
Date of designation
24 May 2000
Locality
Llandygai
Community
Llandygai
Unitary authority
Gwynedd
Country
Wales
Coordinates
53.21530, -4.10710
Cadw reference
23457

Slide toward Today to fade the historical sheet and see the modern map underneath.

David Rumsey Map Collection, Stanford Libraries

5 historical maps cover this location, the earliest the 1896 map "Sheet 7. Ordnance Survey of England and Wales." (David Rumsey Map Collection, Stanford Libraries).

Historical maps covering this location

  • 1896 · Sheet 7. Ordnance Survey of England and Wales. (David Rumsey Map Collection, Stanford Libraries)
  • 1899 · 106 Bangor (Outline) (David Rumsey Map Collection, Stanford Libraries)
  • 1899 · 106 Bangor (Hills) (David Rumsey Map Collection, Stanford Libraries)
  • 1901 · Sheet 9 and 10. (David Rumsey Map Collection, Stanford Libraries)
  • 1919 · Sheet 41. Anglesey. (David Rumsey Map Collection, Stanford Libraries)

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This record in Cadw's own full report ↗

Cadw's description

Located at west end of Llandygai Tunnel; deep cutting to west with large industrial estate on north side.

The Chester to Holyhead line was proposed to improve links with Ireland, the bill being passed in July 1844 with Robert Stephenson as engineer and Francis Thompson of Derby as architect. The tunnel is likely to be by Stephenson with assistance from Mr Foster, the resident engineer for this stretch of the line. Opened 1 May 1848 and taken over by the London & North-Western Railway in 1859. The portal at the east end of the tunnel has been altered and is not included on this list.

Purplish red brick with pink sandstone detailing. Single round-headed arch to tunnel with rusticated voussoirs flanked by raking pilaster buttresses, above which is a corbelled stone cornice with a further band of stonework to the parapet itself; brick soffit to tunnel.

Included as an essentially unaltered early railway structure on the important Chester to Holyhead Railway, the tunnel portal is both architecturally distinctive and a fine piece of railway engineering.

Nearby in the register

Other entries of the same register within about three miles of this one, by straight line.

Designated Historic Asset GIS Data, The Welsh Historic Environment Service (Cadw), 2026-09-07, licensed under the Open Government Licence http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/ Cadw, the Welsh Historic Environment Service · Open Government Licence v3.0
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