At the far end of the reception area were two open shafts sunk into the wall.
The drift mine continued to be worked until 1900, when a shaft was sunk.
The shaft was sunk in 1942 on the site of an older pit that had been abandoned almost 60 years earlier.
The first shaft for a deep colliery was sunk in 1840.
A second shaft was also sunk around this time.
Turning down a side road, we came on a granite-lined shaft sunk 50 feet into the ground.
The tunnel is also notable as being the first for which shafts were sunk during construction.
In 1941, a new shaft was sunk to a depth of 160 metres.
Further shafts were sunk in June 1902 and 1909.
The shaft was sunk a further 610 m below the surface, almost to sea-level.