On this day: December 27

Published On: Dec 26 2012 02:53:05 PM CST   Updated On: Dec 27 2015 01:00:00 AM CST

Charles Darwin embarks on the HMS Beagle, "Howdy Doody" makes its TV debut, Apollo 8 splashes down after orbiting the Moon, and the Soviet Union occupies Afghanistan, all on this day.

OTD December 27 - Cave of the Swallows
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1966: The Cave of Swallows, the largest known cave shaft in the world, is discovered in Aquismón, San Luis Potosí, Mexico. The floor of the cave is a 1,092-foot freefall drop from the lowest side of the opening, with a 1,214-foot drop from the highest side.

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