Sea Ice Runway, Antarctica
Heavily parka'd passengers disembark from a C-17 near the McMurdo Station U.S. science base on Antarctica's Ross Island.
The sea ice airfield—which sags under planes even in the best conditions—is one of seven extreme airports that could make even your hairiest holiday touchdowns seem cushy by comparison.
For instance, at McMurdo flat land is in short supply, which explains why planes take off and land on sea ice in spring—when the region's brutal weather offers a window. (See your Antarctica pictures.)
Usually by December, the sea ice begins to weaken and give too much. The airfield is then dismantled for the year, and planes use another icy runway, on the Ross Ice Shelf, which is operational in the colder months.
(Read a first-person account of what it's like to arrive at the Antarctic base.)
Pictures: World's 7 Most Extreme Airports
From cliffside strips to sea ice runways—these breathtaking, heart-stopping, runways may render your holiday flights cushy by comparison.