The Monument Geyser
Basin has no active geysers, but its 'monuments' are siliceous sinter deposits similar to the siliceous spires discovered on the floor of Yellowstone Lake
. Scientists hypothesize that this basin's structures formed from a hot water system in a glacially dammed lake during the waning stages of the Pinedale
Glaciation. The basin is on a ridge reached by a very steep one-mile (1.6 km) trail south of Artists' Paint Pots.