Walnut Tree (Garth) Tunnel
Walnut Tree (Garth) Tunnel
The Barry Railway Company was developed to transport South Wales’ coal into Barry Docks, breaking the monopoly of the Taff Vale Railway and Cardiff Docks. Work on its network started in 1885 and encompassed 68 route miles by the early 1900s.
One of the later additions was the Rhymney branch, driven northwards from Tynycaeau Junction to Penrhos Junction. Opened in 1901, this featured two significant structures. Walnut Tree Viaduct involved seven lattice girder spans supported by brick piers, 516 yards in length and 120 feet high. This was demolished between 1969-74. Not far from its southern abutment was a tunnel of the same name, occasionally known as Garth.
A footbridge crosses the southern approach cutting just in front of the portal which is stone-built with buttresses either side of the entrance. 490 yards in length, the tunnel’s lining comprises vertical masonry side walls and a segmental arch in brick. Refuges are provided, many with exposed rock at their rear. Though straight at the southern end, the bore curves westwards as daylight returns at the north end. The portal there is of a similar design to its sibling.
Traffic over this section of line ceased on 31st March 1963 following a blaze which destroyed Tynycaeau North signal box. The route was officially closed that summer.
Now gated at both ends, the tunnel has been breached by quarrying, creating a 50-yard air gap close to its centre. The remainder is generally dry and free from clutter.
