Echinus Geyser
Echinus Geyser discharges water at 185 degrees Fahrenheit in Norris Geyser Basin, where USGS measurements recorded highly acidic pH of 3.4 and sulfate concentrations reaching 286 milligrams per liter. Located 156 meters from the Grand Loop Road at 7,510 feet elevation, this thermal feature provides accessible viewing of one of Yellowstone's most acidic major geysers, heating water 150 degrees above ambient temperature.
The geyser occupies the Porcelain Basin section of Norris, where acidic waters and intense thermal activity have created extensive sinter deposits and bleached, thermally altered soils. At 7,510 feet elevation, the area receives 27 inches of precipitation and 137 inches of snow annually. The surrounding landscape shows the characteristic barren, whitish terrain of acid-sulfate thermal areas, with fumaroles and steam vents creating constant atmospheric haze across the basin.
Echinus takes its name from the spiny, sea-urchin-like mineral formations that once characterized its crater and surrounding deposits. The geyser has undergone periods of active eruption alternating with quieter hot spring behavior throughout recorded history, with eruption patterns shifting substantially over recent decades. Norris Basin's thermal features have been systematically documented since the 1870s, making Echinus one of the park's well-studied geysers.
Access via the Back Basin boardwalk trail, a 156-meter walk from parking areas along the Grand Loop Road. The boardwalk remains open typically from May through October, weather permitting. Indian Creek Campground, 18.6 kilometers away, provides reservable sites in a quieter setting below the Gallatin Mountains. Geyser eruptions have become less predictable in recent years, so viewing requires patience and potentially multiple visits to the basin.
Is Echinus Geyser worth visiting?
Best for
- Observing powerful hot springs
- Overnight camping trips
- Winter soaking with dramatic temperature contrast
Not ideal for
- Casual soaking
The water at Echinus Geyser is acidic (pH 3.4). It is notably rich in sulfate (traditionally used for skin conditions and inflammation), chloride (natural antiseptic with skin health benefits), and iron (iron-rich springs may support circulation).
Some links are affiliate links. We may earn a commission at no extra cost to you.
Overview Located about eight miles (13 km) south of Mammoth Hot Springs on the road to Norris, Indian Creek Campground—elevation 7,300 feet (2225 m)—sits near the base of the Gallatin Mountains and offers breathtaking views of Electric Peak. The area offers easy access to fishing and hiking. The campground is away from the main road and provides a quieter, more primitive, experience than many other locations. For reservations at the campgrounds managed by Yellowstone National Park Lodges (Fi...