Diamond Swamp

The lowlands of Diamond Swamp feature lava fields formed 25,000 years ago when molten basalt billowed up through fissures in the earth and spread across a dry lakebed. Before the initial layer cooled, more molten rock thrust it upward, creating some of the most diverse basaltic features found anywhere in the United States. The road leads to Diamond Craters Outstanding Natural Area, a curious array of collapsed craters, lava domes, lava tubes, wrinkled ridges, cones, spires and other formations.

This is a major stop on the Diamond Loop Tour Route.