The Port: Antarctica
Why you'd leave the comfort of your stateroom, we'll never know. But you can stay overnight onshore on the White Continent in a two-person tent, or out in the open in nothing but an insulated sleeping bag (talk about bragging rights). You'll fall asleep to the sounds of heaving glaciers and perhaps whales spouting and feeding in the bay. Don't forget to put on your long underwear — and wake early to see the amazing sunrise.
Who Offers It: Hurtigruten offers overnight camping, often included in the price of the cruise.