If you hear someone say "Ushuaia," don't respond "gesundheit" — but rather "I'd love to!" This adventurer's haven is definitely nothing to sneeze at, because having gone from penal colony to naval base, Ushuaia has worn plenty of hats over the years. Its remote location — way, way down at the bottom of South America — is sometimes described as the end of the world. It's not a joke, but a label that Ushuaia wears with pride, and even has the official photo-op sign so you can prove you made it there. Tierra del Fuego National Park is, naturally, the southernmost national park anywhere, and famous for its beautiful waterfalls, glaciers, snow-capped mountains, lakes and forests… not to mention the exotic wildlife. Speaking of which, the king crab are huge here, and local restaurants let you get so up-close you can taste one. Penguins and sea lions are among the sights, with the local penguin rookery and Sea Lion Island specializing in great views, the kind Charles Darwin may have had when he graced Ushuaia with his presence in the 19th century.