In addition to the name for the nearby section of Yellowstone Lake, the West Thumb section contains a geyser basin, loop trail and a historic ranger station. Grand Loop Road begins here on its path along the lake to Yellowstone Lake Lodge.
West Thumb Geyser Basin Trail
The West Thumb Geyser Basin Trail is a half-mile loop trail near the southeast corner of Yellowstone Lake near West Thumb Junction.
Fishing Cone
Fishing Cone is a cone geyser that once had eruptions as high as 40 feet in the early 20th century. The cone has cooled due to higher water levels in Yellowstone Lake and it is now a hot spring instead. It was given its name because anglers used to boil their catch there. The practice is no longer permitted in the park.
Black Pool
Prior to 1991, this pool’s blue water and cyanobacteria rendered it a dark green or almost black color to give the hot spring in name. A shift in thermal energy in 1991 raised the temperature of the pool and killed the cyanobacteria, resulting in the intense blue color despite the name.
Seismograph Pool
