Coal mining was once the main industry of the Rhondda Valley and the surrounding area. The Big Pit ("Pwll Mawr") colliery ceased production in 1980 but its buildings and machinery were preserved and converted into a museum of mining. Visitors descend into the mine via the 90-m (300-ft) lift shaft to walk through underground roadways, air doors, stables (for pit ponies), and engine houses constructed by past generations of miners.
