GOSA (The Geyser Observation and Study Association) Old Road Group  

Old Road Group: - Map

The dirt trail through this area follows the road bed of the old road that used to lead into the Upper Geyser Basin. The trail connects the main boardwalk system of the Upper Geyser Basin at Morning Glory Pool to Biscuit Basin. Since it is possible to drive to Biscuit Basin, relatively few people use this trail. This area provides some seclusion from the tourists in the Upper Geyser Basin.

There are a few pretty pools, Cauliflower and Artemesia's pool for example, and nice geysers, Atomizer and Artemesia for example, along this trail.

Artemesia Geyser: [Picture] [Map]

Artemesia is a major geyser and has one of the prettiest pools visible in the Upper Geyser Basin. The name is due to the color of some of the sinter around the geyser. The people who named Artemesia thought that the pale green-gray sinter was similar in color to sagebrush (Artemesia).

Artemesia's highly variable intervals range from 9 to17+ hours, durations range from 15-25 minutes and heights can reach 30 feet.

Artemesia occasionally has minor eruptions. It can be years between periods of minor activity. Minor eruptions last about five minutes, requiring about two hours for the pool to refill afterwards. Minor eruptions are often followed by a major eruption about 6 hours later.

Artemesia is next to the old road. The road bed at this point was raised above the geyser. Sitting on the edge of the old road provides an excellent view into Artemesia's large blue pool. Artemesia's eruptions are not overly tall but they put out a huge amount of water and are fun to watch, hear and feel.

What to look for:

After a major eruption, Artemesia's pool drops about two feet. The pool slowly rises and reaches overflow about 5 hours later. From this point until just prior to the eruption, Artemesia overflows gently. As far as anyone has determined, Artemesia gives no indication that it is about to erupt. Suddenly, the water rises and there is a massive overflow. This is fun to watch. The massive overflow lasts about 5 minutes and then the pool starts to boil. It takes a few minutes for the eruption to really get going. Artemesia's eruption is characterized by heavy boiling, not bursting. During the eruption strong underground thumping can be felt and heard as steam bubbles in the plumbing system of the geyser collapse. This strong thumping is one of the unique features of this geyser. It is one of the main reasons many people are willing to wait so long to see its eruption.

Atomizer Geyser: [Picture] [Map]

Atomizer erupts in series. The series consists of 3-5 minor eruptions and culminates in a major eruption. Minor eruptions last about one minute and reach up to 30 feet. The water-phase of the major eruption lasts 8-10 minutes and reaching 40-50 feet. This water-phase is followed by one of the best steam-phase eruptions in Yellowstone National Park. There are only a handful of other geysers, all of them fairly rare, that have louder and more impressive steam-phases than Atomizer.

Atomizer is a cone-type geyser. It consists of two cones each about 3 feet high. The jetting comes from the left-hand cone. The rift-hand cone, or mound, only exhibits activity during a major eruption. This activity consists of the spraying of a fine mist to a few feet. It is this fine mist that gave Atomizer its name.

Atomizer is located behind Artemesia geyser. Unfortunately, there is no way to get a close look at it but it is a fun companion on those long Artemesia waits. The possibility of a major eruption with its accompanying steam-phase, which is easily heard from the trails in the area, makes Atomizer a truly fun, if often overlooked, geyser.

What to look for:

It takes about 4 hours for Atomizer's water levels to recover after a major eruption. Once the water levels recover, Atomizer has brief periods of overflow every few minutes. These periods of overflow continue for about 2-4 hours until Atomizer has its first minor eruption of the series. The interval between each of the minor eruptions is usually about one hour, although the next to the last minor interval sometimes can approach 2 hours. There are usually 6-8 minor eruptions prior to the major eruptions which ends the series. The interval between the last minor and the major eruption is often around one hour but can be as short as 15 minutes or as long as 1.5 hours.

[ Geyser Hill Group - Map ] [ Old Faithful Area - Map ]
[ Castle Group - Map ] [ Sawmill Complex - Map ] [ Grand Group - Map ]
Grotto Group -