Going sea swimming in Iceland will make for an amazing story to tell your friends, and dedicated practitioners agree that alternating between the icy ocean and the toasty hot pot has numerous health benefits. In the wintertime, you can borrow neoprene boots and gloves from the service desk (these make a huge difference), and you can treat yourself to a cup of cocoa from the snack bar afterwards. Fact: it gets worse before it gets better.

2013: City Library

Photo by Julia Staples