MAINZ, Germany -- A 70-year old German man was rescued Tuesday from the Austrian Alps, where he was stuck for six days in a crevasse nearly 10,000-feet above sea level.

The man, who was not named, survived by eating rations of a chocolate bar and drinking melted glacier water, officials said.

Medical officials expressed surprise that he had survived for so long in such icy conditions.

"One of the treating physicians told us that one of the first things the 70-year-old asked for was a beer with a shot of lemonade," said Johannes Schwamberger, spokesman for the hospital in Innsbruck, Austria, where the man was being treated after his rescue.

Climbing alone
The man, who hailed from the southeast German state of Bavaria, had been touring by himself Schrankogel mountain in the central eastern Alpine region of Stubai without the safety of a rope.

"It's a wonder he survived for so long," Gerhard Baumann, from the Austrian mountain rescue team, told NBC News.

"Climbers are always being told not to hike the mountains alone, to be in regular contact with relatives or friends and to be roped at all times, especially on a glacier," Baumann explained.

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'Cold was his biggest enemy'
Rescuers pulled the man out of the crevasse after other climbers had heard his screaming.

"Because the man had no serious injuries, it was not so difficult to pull him out of the crevasse," Baumann said.

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"The man had fallen between 10 and 15 meters (32-50 feet) into the crevasse and was resting on a ledge -- the cold was his biggest enemy," Baumann added.

The man was airlifted to a hospital in Innsbruck, where he is recovering from his ordeal in the intensive care unit. Hospital officials told NBC News that the man has no life-threatening injuries and is in stable condition.

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Doctors were checking his kidneys, to see whether they have been affected by drinking only mineral-free glacier water.

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