• Level No. 1: Situated at a depth of 335 feet (or about 630 feet above sea level), this level extends northwards for 9,200 feet. In 1855, it was linked by cross cuts to St Annal’s Shaft.

• Level No. 2: Located deeper at 470 feet (approximately 160 feet above sea level), this level was driven northward from Shakemantle Land Shaft for 12,950 feet. It was connected to St Annal’s Shaft in 1876.

• Level No. 3: Reaching a depth of 620 feet (about 10 feet above sea level), this level also connects with the Shakemantle Mines. Currently, it is flooded up to just above Level No. 1. During periods of low water, exploration has extended through it to the Shakemantle Mines. Today, Level No. 3 serves as a water supply.

Unattributed trip report in MotFoD

Trip report 1st February 2015. A short walk up the hill behind the houses brought us to the entrance to the mine in a deep scowl (opencast working). The Foresters hadn’t been there for about 6 years as they said after the last visit they never wanted to go there again. When we asked why they said we’d find out.

A short way inside was a gate which took considerable swearing to open, then a ladder pitch of about 7 metres. Immediately we found out what the fuss was about - it was a horror of loose rocks, breakdown everywhere. Tony said you wouldn’t want to be there if there was an earthquake, I said I wouldn’t want to be there if someone sneezed. Tony had a few route finding problems which was a bit tense, but eventually we got into a hading rift which was solid on the left and loose on the right. We eventually came to a sizable chamber with a load of modern rubbish in it
so I guess there is a run-in entrance somewhere. We spent some time looking for the supposed way on but couldn’t find it so made our way gingerly out.

The mine opened in 1835 and ceased operations in 1899. Over its active years, it was expanded through the addition of multiple underground levels and connections to nearby shafts and mines.