Old Faithful Geyser
The first geyser in the park to receive a name, and the most famous.
Plan Around Old Faithful Geyser
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Old Faithful Geyser Details
Old Faithful is a cone geyser and named in 1870 during the Washburn-Langford-Doane Expedition. It was the first geyser in the park to receive a name. Eruptions can shoot 3,700 to 8,400 U.S. gallons of boiling water to a height of 106 - 185 feet (30–56 m) lasting from 1.5 to 5 minutes. The average height of an eruption is 145 feet (44m) high. Intervals between eruptions can range from 45 to 125 minutes, averaging 66.5 minutes in 1939, slowly increasing to an average of 90 minutes apart today. More than 137,000 eruptions have been recorded. Harry Woodward first described a mathematical relationship between the Duration and intervals of the eruptions (1938). Old Faithful is not the tallest or largest geyser in the park; that title belongs to the less predictable Steamboat Geyser. Over the years, the length of the interval has increased, which may be the result of Earthquakes affecting subterranean water levels. These disruptions have made the earlier mathematical relationship inaccurate, but have in fact made Old Faithful more predictable. With a margin of error of 10 minutes, Old Faithful will erupt 65 minutes after an eruption lasting less than 2.5 minutes or 91 minutes after an eruption lasting more than 2.5 minutes. The reliability of Old Faithful can be attributed to the fact that it is not connected to any other thermal features of the Upper Geyser Basin. Between 1983 and 1994, four probes containing temperature and pressure measurement devices and video equipment were lowered into Old Faithful. The probes were lowered as deep as 72 feet (22m). Temperature measurements of the water at this depth was 244 F (118 C), the same as was measured in 1942. The video probes were lowered to a maximum depth of 42 feet (13 m) to observe the conduit formation and the processes that took place in the conduit. Some of the processes observed include fog formation from the interaction of cool air from above mixing with heated air from below, the recharge processes of water entering into the conduit and expanding from below, and entry of superheated steam measuring as high as 265 F (129 C) into the conduit.
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Low
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Nearby Parks Around Old Faithful Geyser
Compare nearby parks around Old Faithful Geyser when deciding whether to expand the route after this stop.
Nearby Points of Interest Around Old Faithful Geyser
Use nearby POIs to quickly expand your options beyond Old Faithful Geyser while the map context is still fresh.
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Old Faithful Geyser
Old Faithful is unquestionably the most famous geyser in the world.
0.1 mi away
Other Thermal Spots
The Upper Geyser Basin has numerous boardwalk and hiking trails.
0.1 mi away
Observation Point Trail
Some of the most unique views of the park's most famous landmark: Old Faithful.
0.1 mi away
Old Faithful Lodge Cafeteria
Located within the Old Faithful Lodge, a cafeteria, bake shop and ice cream shop.
0.1 mi away
Old Faithful Lodge Cabins
The log-and-stone Old Faithful Lodge was built in the 1920 and offers great views of the geyser.
