A few kilometres into Poland from Náchod, in the Kudowa-Zdrój suburb of Czermna, is one of central Europe's strangest interiors: a small Baroque chapel whose walls and ceiling are entirely covered with human skulls and femurs. Some three thousand are on display; another twenty thousand or so lie in the crypt below.
The chapel keeps short opening hours and small group sizes; the warden gives a brief explanation in Polish, with a printed translation in several languages. It is easily reached as a day trip across the border, with a stop in Kudowa for the spa park and a meal.