Boulby’s two shafts are 1,100m deep and lead to hundreds of miles of roadways which descend even further down into the earth. The mine was opened as a potash mine and the rock salt was produced ...
Boulby's two shafts are 1,100m deep and lead to hundreds of miles of roadways which descend even further down into the earth. The mine was opened as a potash mine and the rock salt was produced as ...