Old Faithful Bench Mark Medallion

Did you know that Old Faithful, discovered by the Washburn, Langford, Doane Survey Expedition in 1870, is named for its predictability? This iconic geyser erupts roughly every 91 minutes, displaying the regularity that inspired its name. The geothermal activity that creates Old Faithful is part of Yellowstone's expansive volcanic system, which includes the massive Yellowstone Caldera—a caldera formed by a colossal eruption around 640,000 years ago, spanning 35 miles by 45 miles.

Furthermore, Old Faithful is not just a solitary feature; it is surrounded by a complex network of geothermal phenomena. The unique interaction between groundwater and the magma beneath the surface generates spectacular eruptions and a diverse array of hot springs, fumaroles, and mud pots.