Chromatic Pool

Overview

Chromatic Pool is a compact, vividly banded hot spring in the Upper Geyser Basin. Its blues, greens, yellows, and oranges are created by heat‑loving microbes thriving at different temperatures around the pool’s edge. The center stays clearer and more blue, while cooler margins support colorful microbial mats. The pool is about 30 feet across and averages roughly 133°F—beautiful, but scalding.

Location and What You’ll See

You’ll find Chromatic Pool about 150 feet west of Beauty Pool, and both sit right beside the boardwalk for easy viewing. These two springs are known to “see‑saw”—water level rises in one as it lowers in the other during periodic shifts in the system. From Chromatic Pool, a color‑streaked runoff channel flows north, then bends west toward the Firehole River. Expect dynamic conditions: water levels, runoff patterns, and even color intensity change over time.

Getting There

Reach it via the Upper Geyser Basin boardwalk on an easy 15–20 minute walk from two large parking areas serving the basin. The wooden paths bring you close enough for detailed views without leaving the trail.

Best Times to Visit

Colors pop most when the surface isn’t shrouded in heavy steam. If it’s steamy, wait for a breeze and try different angles along the boardwalk. Pair your stop with nearby Beauty Pool for a quick, satisfying loop.

Safety and Etiquette

Stay on the boardwalk—the ground off‑trail can be thin and unstable over near‑boiling water. Don’t throw coins or objects into the pool. This is not a soaking area; temperatures and chemistry can be dangerous. Wildlife like bison and elk may pass through—give them space and never approach or feed them.

Facilities

There are no facilities at Chromatic Pool itself. The nearest on‑trail option is a vault toilet at Morning Glory Pool. For flush restrooms, use the Old Faithful area before or after your walk.