Lissummon, a long, abandoned tunnel hidden in the Northern Ireland countryside

The island of Ireland is known for its beautiful green landscapes, but amidst them you can find some surprises.

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In southeast Ulster lies the city of Newry. To the northwest, off the A-28, is the Lissummon Road, a rural track that runs through the countryside. There, hidden in the vegetation, is an abandoned old tunnel 1,650 meters long (a little over a mile). According to the blog Forgottenrelics.org, The Lissummon Tunnel began construction in 1861 as part of a new railway line connecting Newry and Armagh. The tunnel was lined with masonry and built in a perfectly straight line, with a gradient of 1:75 to the north.

The Lissummon railway was the longest railway on the island of Ireland. The first train passed through it on 25 August 1864. The tunnel was built with shelters to allow any passers-by to get to safety if they met a train. There is one shelter for every 20 yards (18.28 metres) on the north side of the tunnel. Passenger trains stopped running through the tunnel in 1933. Freight trains continued to use the tunnel until it was abandoned in 1957. The tunnel is in good condition despite being abandoned for 68 years, but it does leak water. Yesterday, Stephen J. Reid posted a video of himself walking through it:

You can see some screenshots from this video here. Here we see the southern entrance to the tunnel, which had a single rail track. The tunnel is fenced to prevent vehicle access.

The part of the tunnel closest to the south exit. It's in good condition, although there are small streams of water on the floor. We can see a tiny white dot in the background: the north exit.

The central section of the tunnel is the wettest area. There are water leaks that make it seem like it's raining inside the tunnel, as you can see in the video. The air is saturated with moisture.

The northern exit of the tunnel. The immediate area is swampy and it is best to be well prepared with rain boots to traverse it.