A pingo is a type of hill found in arctic regions, including Canada and Greenland, that are filled with ice. They are a result of successive freezing of ground water, pushing upward and are located in permafrost regions. The term is also used for holes that can result when one collapses. the ice melting. Such hills have grown to a height of over 200 feet.
Pingos may be found on other solar system bodies, and some features on icy moons are theorized to be pingos.