Melting water creates these marble-like ice caves in the Vatnajokull ice flow in Iceland.
A photographer braved freezing conditions to capture the caverns, which can be deadly because of the shifting ice. “The glaciers are constantly moving and changing their formation,” said the photographer. (Photo: Skarphedinn Thrainsson / Caters News)
The picture above is taken from Harbin International Ice and Snow Festival. Visitors take pictures of buildings made from blocks of ice for the Harbin International Ice and Snow Festival in Harbin in northeastern China's Heilongjiang province, on Wednesday, Jan. 4, 2012. The festival is scheduled to officially open on Thursday night, Jan. 5. (AP Photo/Andy Wong)