
These iron rings were installed at vantage points along routes around the Upper Rock to allow heavy equipment, particularly guns, to be pulled up and down the Rock. Initially this was all done with muscle power with the aid of pullies and block. By the end of the 19th Century, steam traction engines were assisting.
A hole was drilled in rock and then molten lead poured in, before the ring was fitted.

These iron rings were installed at vantage points along routes around the Upper Rock to allow heavy equipment, particularly guns, to be pulled up and down the Rock. Initially this was all done with muscle power with the aid of pullies and block. By the end of the 19th Century, steam traction engines were assisting.
A hole was drilled in rock and then molten lead poured in, before the ring was fitted.
