There are a number (about 21) of deep mineshafts on the Thorswood nature reserve, some are in a state of collapse and others are capped.
The majority of exploration has taken place in one of the main hauling shafts referred to as King Shaft at SK112470. The King Shaft is approximately 95m deep but has been previously documented to have larger workings at approximately -130m. The accessible workings are quite extensive and have areas of historical interest such as wooden ladder ways, draft doors, hobnail boot prints, miners snapping stools etc,
Access to the site is controlled by Staffordshire Wildlife. Information obtained from an Eldon Pothole Club Newsletter dated Spring/Summer 2006.