Old Faithful is an iconic symbol of Yellowstone National Park, a UNESCO World Heritage site. The famous geyser is located in the Upper Geyser Basin, the largest concentration of geysers in the world, and is surrounded by buildings in the Old Faithful Historic District.
Why is it named “Old Faithful”? It’s one of the most predictable geysers in the world. In 1870, the Washburn Expedition named it for its near-regular eruption times. Legend has it that it erupted every hour but that’s not true. Old Faithful erupts every 35 to 120 minutes with eruptions lasting anywhere from 90 seconds to five minutes. The interval between eruptions has been steadily increasing over the years.
By the Numbers
When Old Faithful erupts, it shoots a stream of boiling water into the air anywhere between 106 and 185 feet high. 3,700 to 8,400 US gallons of water are expelled during each eruption. The water temperature is about 199°F but can reach up to 244°F at a depth of 72ft.
As Old Faithful is about to erupt, it shoots out short bursts of water. After a few moments, the bursts continue and the stream of water gets taller and taller until the full eruption commences.
A viewing platform with benches has been set up at a safe distance from Old Faithful. Predicted eruption times are displayed in the area around the geyser, such as the visitor center. As we sat and waited for it to erupt, we were making friendly wagers with other visitors as to the exact time of eruption.
Geysers Around Old Faithful
A walkway around Old Faithful gives 360 degree views of the geyser. It also passes by the Firehole River and some small springs nearby.
Chinese Spring is 12.5ft deep with a temperature of about 200°F. The first known eruption of the spring (and its namesake) was in 1880, when a Chinese laundry worker pitched a tent over the spring and used it to wash clothes. He added soap to the spring and it erupted, spewing out the laundry and collapsing the tent. All known eruptions of the spring have been caused by humans, and they can reach a height of 20ft lasting two minutes.
East Chinaman Spring sits near Chinese Spring. It contains a pool of permanently boiling water. Across the Firehole River, Cascade Geyser on Geyser Hill is visible. It’s named for the nice cascade of water flowing down into the river. Its last known eruption was in October 1998. It can spray water 30 to 45 feet into the air.
Blue Star Spring is about 6ft deep with dimensions of 10ft x 9ft and a water flow of four gallons per minute. Many items have been removed from the spring as a result of frequent vandalism. Also, a baby bison fell into the spring in 1996 and was killed by the hot water. The skull can still be seen at the bottom. Apparently, the spring smelled like beef soup for a while after the incident.
Old Faithful isn’t the biggest or tallest geyser in Yellowstone, but it’s definitely one of the best to watch and a must-see in the park. It’s an experience that I’ll never forget.