Barnsley, England, July 5th 2020.
After doing some searching online for unusual free things in my area, I came across the Thurgoland Tunnels.
The 924ft long tunnels are located along the Trans Pennine Trail, a walking/ cycling path which runs along the old Sheffield, Ashton-Under-Lyne and Manchester railway line. The line opened in 1845 but closed in 1983.
Only one of the two tunnels is open, the other is blocked off. If you clap your hands or make sound whilst in the tunnel, you will hear an unusual reverberating sound due to the acoustics in the tunnel.
If you intend just to visit the tunnel, I would suggest parking under the bridge on Cote Lane if you travel by car. The entrance to the trail is marked and is located at the side of the bridge.