Morlais Tunnel, Merthyr Tydfil
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. John Charles Mackay won the contract to build it.
The tunnel went through limestone and millstone grit. Three shafts were dug to speed up work. Dynamite was used with the Ingersoll drill. This machine used compressed air. Mr Cross from Cardiff managed its use. 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.
In December 1876, Rees Jones stole two waistcoats. They were drying on Henry Downes' washing line. Jones, a shaft sinker, was jailed for 21 days. He had to do hard labour. 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.
From the north, the tunnel curves south for 155 metres. It bends and then, it runs straight for a long way. The tunnel has stone side walls and a brick arch. There are escape spots 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. The three shafts are still open. The middle one lost its top, which now lies in the tunnel. 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. A long retaining wall holds up the approach on the west side. A short wing wall sits on the other side. The south portal is more impressive. However, time and damage have taken their toll. Ivy now covers the headwall. It once had a stepped parapet with carved coping stones. The date stone was above the arch's centre. If it remains, plants now hide it. Five brick rings are visible on the face. Three are curved for extra style. The wing walls descend from the portal. They stretch into the approach.
