Over 10,000 years ago about a third of the land surface was covered by ice. Today a tenth is still covered in ice. Ice sheets can cover very large areas and can be very thick. The world’s largest ice sheet covers most of Antarctica and is very slow moving.
Antarctica covers about 5,400,000 square miles (14,000,000 square km) It is larger in area than either Europe and Australia. However, Antarctica would be the smallest continent if it did not have its icecap. This icy layer, which averages approximately 7,100 feet (2,200 m) thick, increases Antarctica’s surface area and also makes Antarctica the highest continent in terms of average elevation.
Glaciers and ice sheets sometimes give up their secrets centuries later. Thawing ice has revealed the bodies of people who fell into crevasses hundreds of years ago. The ice preserved their clothes and their internal organs.