The Diga di Luzzone is both a working dam and one of the largest artificial climbing walls in the world. Bolted in the 1990s, this spot in Switzerland is home to one of the two largest man-made climbing routes in the world, a 540-foot, five-pitch monster that curves its way up the side of the Luzzone dam. As climbers go through the pitches, the concave wall changes character, starting off slabby, then straightening out to vertical.

Visitors who want to throw down on the dam will need to pay 20 Swiss francs each to get the keys to unlock the ladder that crosses the first section.