Artesia Geyser is a small but active geyser in Yellowstone National Park’s Lower Geyser Basin, beside Firehole Lake and within the Black Warrior Group of thermal features. Its most distinctive trait is persistent activity: as a perpetual geyser, it never fully stops discharging from at least one of its two vents. Those vents point in different directions, giving its eruptions a changing form. Though usually modest, its behavior has shifted over time between steady spouting and roughly minute-spaced bursts, including stronger phases in 1999, 2012, and again by 2018. Its accessible setting has made it part of a closely observed geothermal area.

Mammoth, Wyoming · USA