Bell pits

Remains of bell pit mining, a primitive method of mining coal and ironstone where the coal lies near the surface on flat land. A shaft is sunk to reach the ironstone and coal which is then excavated and removed by means of a bucket (much like a well). No supports are used and mining continues outward until the mine becomes too dangerous (or collapses) at which point another mine is started. The pits here are from 13th century.