March 2025
Another one from my solo weekend in South Wales, from the northern portal, the tunnel curves south for around 155 metres and then runs straight. The tunnel has stone side walls and a brick arch refuge points in the walls. Old cable hangers are still on the east side, just above the wall's base. The first air shaft is 350 metres from the north end. Water pours down it. The others are drier, at 540 and 720 metres. Above ground, the walls around them have sloping sides, they also have square labels under the top bricks. Above this, sandstone holds domed iron grilles. The centre and south-east shafts are Grade II listed. Overlooking Morlais Tunnel Junction stands the north portal. It's built from stone and adorned with moss and small trees.
History
On 1 January 1873, Dowlais became the end of the London & North Western Railway's line. It ran from Abergavenny and had opened in stages since 1862. The first part of the line went to Brynmawr. Next, the company wanted a line into Merthyr Tydfil. The Brecon & Merthyr Railway feared competition from this railway giant. It accepted the L&NWR's offer to pay half the building costs. This gave them a joint stake in the line around the town's west side, entering from the south. To complete this plan, the L&NWR needed permission for a link. It would connect their line at Penywern Junction and the B&M near Vaynor. Approval was granted in July 1874. This connection was short, just over two kilometres. Yet, it needed complex engineering to cut through the hill. Half of it went through the Morlais Tunnel. The tunnel was 950 metres long. At its deepest, it was 25 metres below ground. John Gardner, a civil engineer, managed the project for the London & North Western.
The tunnel went through limestone and millstone grit. Three shafts were dug to speed up work. Dynamite was used with the Ingersoll drill. Trials showed the machine was much faster than hand drills. It made holes in the rock at 50cm every ten minutes. After the pilot tunnel, the full dig moved forward. The London & North Western's trains first reached Merthyr High Street Station on 1 June 1879. To celebrate the tunnel opening, important people posed for a photo. It was taken at the tunnel's south entrance, under a stone in the wall. The Morlais Tunnel closed on 6 January 1958. Since then, walls with access doors and air holes block both ends. Before it was sealed, six cars were driven inside. They were later set on fire.
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Fujifilm X-T5, 10-24mm f4 R OIS WR
