Aurum Geyser

Aurum is a small geyser on Geyser Hill. Its main vent boils constantly in a shallow pool, ringed by raised, knobbly sinter that almost forms a cone. A few smaller vents steam across the pale mineral ground. The rim and the rounded mineral beads are the details to notice; if you take a photo, include some of the runoff pool so the little cone makes sense.

Aurum sits along the Geyser Hill boardwalk loop in the Upper Geyser Basin, reached from Old Faithful. The full loop is about 1.1 miles; that is the loop distance, not the walk from its start to Aurum. With more than 50 geysers on the hill, I’d treat Aurum as a small detail on a wider thermal walk rather than plan a separate outing around it. The hill also gives you a vantage point for an Old Faithful eruption. Aurum’s pool boils all the time, but eruptions are irregular, so count one you catch as luck. Stay on boardwalks and designated trails: hydrothermal water can severely burn.

An earthquake in 1983 changed Aurum’s pattern. Before it, the geyser boiled actively but eruptions were rare; recorded intervals afterward ranged from 22 hours to more than two weeks. An eruption can reach about 20 feet and last around 70 seconds, but those intervals describe past behavior, not when the next one will happen. More broadly, rain and snow seep deep into Yellowstone’s cracked volcanic plumbing, heat underground, and rise back to the surface through geysers and springs.