Oblong Geyser

Deep-blue pool geyser that floods the Firehole River during eruptions

InsideYellowstone National Park

Overview

Oblong Geyser sits along the Firehole River in the Upper Geyser Basin, a short, straightforward boardwalk walk from the Old Faithful area. It’s a deep‑blue pool with a raised sinter rim and distinctive sawtooth‑textured geyserite. Eruptions aren’t the tallest in the basin, but they’re satisfyingly forceful and dump a remarkable volume of water into the river.

Geyser Activity

Typical interval is about every 3–7 hours, with eruptions lasting 5–7 minutes and reaching roughly 25 feet. It’s not one of the park’s regularly predicted geysers, so consider it a pleasant bonus rather than a guaranteed show. The big payoff is the sheer amount of water surging toward the Firehole—fun to watch from the boardwalk.

Getting There

Park at the main Old Faithful/Upper Geyser Basin lots and follow the paved paths and boardwalks through the basin toward Grand Geyser and the river. The route is flat, obvious, and lined with other noteworthy features, so it’s easy to fill time while you wait for activity.

What To Expect

A photogenic, deep‑blue pool framed by a raised sinter rim.
A wide, powerful eruption plume rather than a sky‑high jet.
Water spilling directly into the Firehole River, sometimes spreading into shallow terraces around the pool.

Best Time to Visit

Go early or late in the day for lighter crowds and better parking around Old Faithful. Midday is the busiest. Because Oblong isn’t predicted, check day‑of predictions for nearby major geysers (from the park) to help you time a broader loop through the basin while keeping an eye on Oblong.

Facilities and Conditions

Full services—flush restrooms, food, water, and lodging—are clustered in the Old Faithful developed area next to the basin. Boardwalk segments occasionally close for maintenance; detours are usually short, but it’s smart to check park updates the morning you visit.

Safety

Stay on boardwalks—thermal areas can be thin‑crusted and dangerous. Surfaces get slick when wet. Supervise kids closely.

Wildlife Notes

You’re unlikely to spot headline wildlife in the thick of the Upper Geyser Basin. If wildlife viewing is a priority, plan separate early‑morning or evening forays to classic valleys elsewhere in the park.

Pros

Easy boardwalk access from Old Faithful with full services nearby
Frequent, short eruptions with a powerful surge into the Firehole River

Cons

Not a predicted geyser, so waits can be hit-or-miss
Occasional boardwalk maintenance closures can force short detours

Tips

Use day-of park predictions for nearby major geysers to pace your visit while keeping an eye on Oblong.
If you’re waiting, loop past Grand, Riverside, and Grotto to maximize your chances of catching something erupt.
Plan for early morning or late afternoon to avoid the densest boardwalk crowds.
Stand upwind during an eruption unless you want a mineral-rich misting.
Check for temporary boardwalk closures the morning you go; detours are common but manageable.