Wieliczka Salt Mine

Wieliczka lies on Kraków's south-eastern edge, and its salt workings are inscribed by UNESCO as part of the Wieliczka and Bochnia Royal Salt Mines. The tourist route takes you down wooden stairs into chambers shaped by miners over centuries, with salt statues, timber supports and chapels cut into the rock. Because the visit is underground, it works as a rainy-day or winter option.

It is easy from Kraków: the Koleje Małopolskie airport line continues to the mine, and the mine's own site lists other ways to get there. We'd book a timed ticket ahead in summer and allow half a day with travel. Wear comfortable shoes, because there are a lot of steps, and check the mine's site for accessibility and the current route before you go.