Don a hard hat for a 45-minute tour of St-Nectaire's Roman baths, deep in a cave that glimmers with damp limestone. Two-thousand years ago, these man-made caverns were used as a natural spa on account of their naturally 22°C, mineral-rich waters. Little remains of the Roman baths, rediscovered in the 19th century, though it's an interesting subterranean ramble.
There are usually five tours daily (11.30am, 2.30pm, 3.30pm, 4.30pm and 5.30pm).