Pocket Basin is one of the least-known and little-visited thermal basins in the valley. It's actually a miniature caldera, originally created by a hydrothermal explosion that must have been roughly on the scale of an atomic bomb. The basin isn’t on the scale of the more famous thermal features further south, but this is one place you can explore away from the boardwalks and parking lots. Remember, however, to take the normal precautions when approaching any thermal feature.
The northern trail leads past the belching mud pot of Grotto Spring and inviting Baby Bathtub Spring to the River Group, a collection of geysers and hot springs that includes Cavern Spring, Bath Spring, Azure Spring, Diadem Spring and Cone Spring. Across the river is Mound Spring, which erupts every half-hour or so. The southern trail leads to two lovely pools and then continues for another couple of minutes to a collection of riverside hot springs.
