November 27, 2007—The Antarctic cruise ship Explorer sinks after it apparently hit an iceberg about 547 miles (880 kilometers) southeast of Ushuaia, the southernmost Argentine city, on November 23, 2007.

All 154 passengers and crew on the ship were rescued with assistance from the National Geographic Endeavour and the 700-passenger Norwegian tour ship Nordnorge.

The sinking of the Explorer has raised concerns about the effects of tourism in Antarctica, which has surged in recent years.

(The National Geographic Endeavour is operated by Lindblad Expeditions in partnership with the National Geographic Society, which owns National Geographic News.)

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