The Maclaren River flows from the Maclaren Glacier south to the Susitna River and then into Cook Inlet just west of Anchorage. Vegetation at this elevation is low-growing alpine tundra. Look for pikas, ground squirrels and ptarmigan. Road construction in 1957 cut into the partially collapsed palsa on the south side of the road and initiated its deterioration. A palsa is a small dome-like frost mound, usually 10 to 20 feet high, containing peat.
Closer examination reveals individual ice and peat layers characteristic of a palsa.
Several small lakes and depressions in this area were formed when chunks of ice broke off retreating glaciers and were buried in the glacial debris. The ice eventually melted, leaving circular-shaped depressions called kettles. The Maclaren Glacier is about 16 miles north. The Crazy Notch was formed by the actions of ice and water. Crazy Notch was created when a glacial stream cut through the moraine.