Itching to go where no man has gone before? Or at least where very, very few have? Then look into an Antarctic Circle expedition. Many Antarctic trips keep you on the Antarctic Peninsula, which has the mildest temperatures on the continent, but only a few allow you to travel south of the Antarctic Circle, the final place on Earth to be explored, and what many consider the least-known realm on the planet. During this trip, the sun will never set and you may spot icebergs as long as a city block drifting by. You'll see the requisite penguins and seals, and may also catch a glimpse of Humpback, Minke and Orca whales. You'll also be able to visit research stations on Adelaide Island. But the best part is that those who are brave enough can get off the ship and mountain-climb, cross-country ski, sea-kayak among the whales and even camp overnight [source: Quark Expeditions].