Geyser Hill Loop Trail

Geyser Hill Loop Trail is a 1.2-mile circuit from the Old Faithful viewing-area boardwalk. It includes the paved approach across the Firehole River, a roughly 0.5-mile boardwalk lap on Geyser Hill, and the return to the starting access. Allow about an hour, longer if you stop to watch a geyser. The footing is easy, but the features are close together and worth a slower look. More than 50 geysers sit on this hill, so it is a strong choice when you want to get among the springs without taking a long walk through the basin.

Start from the Old Faithful viewing-area boardwalk and follow the paved path east to the bridge over the Firehole River. Continue to the Geyser Hill junction and take the boardwalk circuit; it closes back at that junction, then you retrace the approach to Old Faithful. The 0.5-mile figure describes the hill circuit by itself. With the approach both ways, plan on about 1.2 miles overall; the half-mile figure is just the hill circuit. Observation Point branches off as a separate uphill outing, and the Morning Glory Pool walk continues elsewhere in the basin; neither is part of this loop.

The western side passes small Anemone Geyser, Beehive Geyser and the Lion Geyser group. Beehive has a small nearby feature called the Indicator; when it erupts, Beehive may follow roughly 10 to 20 minutes later. That is a useful hint, not a timetable: these geysers do not run to a dependable schedule. Geyser Hill also gives you a different angle back toward Old Faithful, so look across the basin as you go.

The other side passes Aurum and Giantess geysers, with Heart Spring and Doublet Pool among the vivid water features on the hill. These are not one big viewing platform; the circuit moves between individual pools, low cones and mineral basins. Take the time to stop at the boardwalk viewpoints rather than trying to see every feature at a glance. The separate Observation Point trail climbs above the basin for a broader view if you want more elevation and a longer walk.

Some of the bright bands around the pools come from thermophiles, microscopic organisms adapted to hot water. The hottest water supports colorless or yellow thermophiles; orange, brown and green appear in cooler water. These microscopic organisms create the visible bands around the pools, and their colors change with temperature. Stay on boardwalks and designated trails; the hydrothermal water can cause severe burns.

The rounded hills around Old Faithful are remnants of rhyolitic lava flows. Later glaciers left layers of till beneath the geyser basins, where water can collect before moving through the heated rock. That combination helps explain why a compact hill can hold so many springs and geysers. With more than 50 geysers, the hill is the fourth-largest geyser field on Earth.

This is an easy addition while you wait for an Old Faithful or Grand Geyser prediction, but do not plan the walk around a promised eruption. The Old Faithful Visitor Education Center is a separate stop nearby, with geology exhibits and films. Pets, including carried pets, are not allowed on Yellowstone boardwalks, trails or thermal areas; trained service animals are allowed and must be leashed. Keep to the boardwalks and designated trails: hydrothermal water can cause severe burns.