At over a mile wide, the Carbon Glacier cirque is the largest in the Cascade Mountains.

[4] The headwall of the cirque is the prominent Willis Wall landform.

Carbon Glacier is accessible from the northwest Carbon River entrance of Mount Rainier National Park, just outside the town of Carbonado, Washington.

The glacier is accessible on foot via an 8-mile (13 km) hike from the Carbon River entrance of Mt.

The road and trail is currently washed out in several areas due to flooding of the Carbon River in 2006.