The Bochnia Salt Mine is the older and quieter sibling of the more famous Wieliczka and, since 2013, also a UNESCO World Heritage Site. Production began in the 13th century, making it the oldest continuously worked commercial company in Poland; the works closed only in 1990, after almost 750 years.
Tours descend by lift to around 250 metres below the surface and run through an extraordinary sequence of chambers: an underground lake you cross by boat, the Chapel of St Kinga carved entirely out of rock salt, a 140-metre slide between levels, and a banqueting hall used for weddings. The longer "overnight" tour lets you sleep down in the mine. Visits run year-round and the underground temperature is a constant 16°C — bring a fleece.