This 634-yard S-shaped tunnel was built in1874 but saw no use until 1885, and even then only until 1917, it is thought to only have carried private GWR trains and PW vehicles, on the 'unopened' extension of the line that was never used.
The facility was used as a bomb store in WW2, it stored depth charges, torpedoes and mines from ROF Swynnerton, after the war it what used as a mushroom farm and more recently i believe it is being used to store equipment connected to the the Lea Bailey railway and Goldmine just around the corner.