Set in a beautiful wooded estate, this is the only known Roman goldmine in the UK. The exhibition and the mining machinery above ground are interesting, but the main attraction is the chance to go underground on a guided tour of the old mine workings. Back at the surface there's a sediment-filled water trough where you can try your hand at panning for gold. Audio guides for individual tours are included with admission.
The Romans left around AD 120, but the locals carried on for a couple of hundred years more. Mining recommenced with the Victorians, and by the time the mine was finally closed down in 1938 the works employed more than 200 men. There are up to 10 tours per day of either the Roman or the Victorian workings (and occasionally both).