Mount Mazama is a destroyed stratovolcano in the Oregon part of the Cascade Volcanic Arc and the Cascade Range located in the United States. The volcano's collapsed caldera holds Crater Lake, and the entire mountain is located within Crater Lake National Park.

Mazama was destroyed by a volcanic eruption that occurred around 5,677 (± 150) BC. The eruption reduced Mazama's approximate 12,000-foot (3,700 m) height by around a mile (1600 m). Much of the volcano fell into the volcano's partially emptied neck and magma chamber. At 8,159 feet (2,487 m), Hillman Peak is now the highest point on the rim.