The Trollkirka is no ordinary church, but a cave made of marble and limestone, where an underground river flows and also a waterfall provides spectacle. You follow a 1.5-hour hiking trail to the Trollkirka. This is a tough and steep route that requires good shoes. The cave is surrounded by nature and is 70 metres long. At the end of the cave is the waterfall that comes down into a white marble bowl. Beyond the cave is a lake where you can swim. You park at the RV64 and follow the signs to Trollkirka. This is about a two-hour drive from the flats. Bring a torch, this is really necessary. The cave is pitch-dark, uneven and unlit.