The Marble Caves is geological formation of unusual beauty. These caves have formed in a pure marble and are bathed in the deep blue water of General Carrera Lake. Chile, the Marble Caves are some of the most impressive attractions of Patagonia.
Beautiful stripes in the landscape of the Quebrada de Humahuaca, a narrow mountain valley located in the province of Jujuy in northwest Argentina, miles north of Buenos Aires. It is about 96 miles long. - photo from Geology IN