Site Records


Site Name: Tregarth Tunnel

East of Tregarth Village
West of A5
North side of Afon Ogwen bridge
OS Grid Ref:
SJ610678 (South Portal)

Sub Brit site visit 30.1.2013

[Source: Les Fifoot, John Wilson & Paul Wright]

Tregarth tunnel is located on the former London & North Western Railway (LNWR) Bethesda branch, a 4 mile 26 chain long single track line that linked the village of Bethesda to the Chester and Holyhead main line at Bethesda Junction (52 chains to the east of Bangor). Between Bethesda Junction and Bethesda the line climbed by over 300 feet which meant that there were steep gradients. The Bethesda branch was authorised in 1880. It was engineered by Edward Walter Nealor Wood, C.E. and opened to passenger traffic on 1 July 1884. Goods trains started to run on 1 September 1885.

Tregath tunnel south portal on 30 January 2013.
Photo by Paul Wright

The tunnel is a single bore and 279 yards in length. In the main it is lined with brick but there are sections that are lined with slate.

The south portal is directly under a road and consists of a skew arch constructed from blue engineering brick. Above the arch there is ledge constructed from sandstone and above it more brick. Immediately to the north of the north portal there is an arched bridge which carried the line over the Afon Ogwen.

The north portal is decorative compared to that at the southern end. It is constructed from stone blocks and includes a dressed stone lintel above the tunnel mouth. Around the arch of the mouth a different colour stone has been used.

An interesting feature of the inside of the tunnel is wooden marker boards that indicate the length. They are numbered 1 to 8 and are placed at intervals of one chain.

The Bethesda branch lost its passenger trains on 3 December 1951 and closed completely on 7 October 1963.

The Tregarth tunnel was found to be in good condition during a Sub Brit site visit on 30 January 2013.

Looking south towards Bethesda from the south portal at Tregarth tunnel on 30 January 2013. The Afon Ogwen bridge can be seen beyond the tunnel:
Photo by Paul Wright

The north portal of Tregarth tunnel on 30 January 2013:
Photo by Paul Wright

Looking north-west towards Tregarth from inside the Tregarth tunnel on 30 January 2013:
Photo by Paul Wright


A refuge point inside the Tregarth tunnel on 30 January 2013:
Photo by Les Fifoot


A pulley wheel inside the Tregarth tunnel that would have supported a signal wire:
Photo by Les Fifoo
t


Looking south towards Bethesda from inside the Tregarth tunnel on 30 January 2013:
Photo by Les Fifoo
t


Wooden distance marker inside the Tregarth tunnel on 30 January 2013. There are eight such marks inside the tunnel:
Photo by Les Fifoo
t

Looking south towards Bethesda from inside the Tregarth tunnel on 30 January 2013:
Photo by Paul Wright


At the south portal of Tregarth tunnel a road passes over. Above the road is the track-bed of the Penryhyn Railway. The retaining wall of that railway can be seen above the tunnel:
Photo by Les Fifoo
t

The south portal of Tregarth tunnel looking north from the Bethesda side of the Afon Ogwen
bridge on 30 January 2013:
Photo by Paul Wright


Click on thumbnail to enlarge


[Source: Les Fifoot, John Wilson & Paul Wright]

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Last updated: Monday, 04-Feb-2013 07:01:46 GMT
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