The Toutle River has become one of the most popular rafting trips in the state because of its exciting and constantly changing rapids and unique environment carved from the mud and ash deposited by the 1980 eruption of Mt St Helens that irreversibly altered the river channel and surrounding lands. The unstable material around the river means that its course, challenges, and hazards are never the same. However, this stretch has consistently good rapids, especially in the section known as Hollywood Gorge, where the channel narrows between basalt cliffs. When the river is not in a tight spot, it is highly braided with constantly shifting channels.