GOSA (The Geyser Observation and Study Association)

Lower Geyser Basin

Backcountry Thermal Areas


Please read the WARNING about traveling safely in backcountry thermal areas.

The Lower Geyser Basin besides containing the easily accessible thermal areas along the Firehole Lake Drive and the Fountain Paints trail, also contains a number of backcountry thermal areas. Some of these areas are easily accessed while others require a short hike. Some, because they are dangerous and/or vissible from the park roads are closed to the public.


Kaleidoscope Group

Kaleidoscope Geyser

Firehose and Kaleidoscope Geysers as seen from a pull out along the main road.

Unfortunately, the Kaleidoscope Group is closed to all foot travel. Only a few lucky researchers are allowed into this highly unstable and dangerous area. But, it is possible to observe most of the activity here from a distance. The Kaleidoscope Group is located on the flats below Fountain Geyser and can easily be watched from either the Fountain Overlook or from one of the pull outs along the main road. For much of the 1990's, the Kaleidoscope Group has been highly active. It contains a surprising number of major geysers including: Kaleidoscope, Drain, Honeycomb, Deep Blue and some major geysers which still don't have names. During the late 90's, it was common wisdom that if you watched the area for two hours, you were almost guaranteed to see at least one and frequently a number of major eruptions from geysers in the area. Don't be fooled by the fact that you can't get close to this area. It is one of the most fascinating and highly active groups in the park.

Imperial and Spray Geysers

Imperial and Spray Geysers are located in the far western corner of the Lower Geyser Basin. There are various routes to the geysers but the shortest trail starts from the steel bridge just south of Midway Geyser Basin. The trail goes behind Grand Prismatic Spring, by scrambling up the hil beside the trail it is possible to get a good veiw of this large spring. At a junction