Iceland's Silfra fissure is the only place in the world where you can swim between two tectonic plates. It is a crack between continents formed because of the tectonic plates pulling apart. Some of the openings are so narrow that you can touch both sides at once, i.e. you can be touching the North American and Eurasian continents at the same time. Not only that, but it’s also where you’ll find some of the clearest water in the world. The Silfra fissure is located in Thingvellir National Park, in southwestern Iceland, and it was designated a UNESCO World Heritage Site in 2004.