Shades of ultramarine, turquoise and sapphire attract visitors from far and wide to Blue Pool along the McKenzie River Trail, making it one of Oregon’s most popular hikes.

Officially known as Tamolitch Falls, the hike measures 2.1 miles one-way from the trailhead to the viewpoint. But don’t be fooled by the short distance. There’s rocky terrain to navigate and several hundred feet of elevation gain on this hike, which is rated moderate. The total distance will also run longer than 4.2 miles if hiking from the lookout down to the pool.

A kaleidoscope of blues

The body of water at the Tamoltch Falls viewpoint is mesmerizing, colored with blues I can’t recall seeing anywhere else in nature.

Its otherworldly hues are the result of a natural dam. Lava flowing from Belknap Crater 1,600 years ago buried a 3-mile stretch of the McKenzie River, according to the U.S. Forest Service. The river disappears at Carmen Reservoir and resurfaces at Tamolitch Falls, where it seeps up to the surface through porous lava.

Proceed with caution

Upon summiting the trail last month, I noticed a neon orange ribbon stretched across the trail. A woman donning a helmet and a red shirt that read “mountain rescue” assured me I was headed in the right direction, as she gestured to skirt the ribbon.

I trekked around the ribbon to an overlook of the pool. While encountering fellow hikers had been intermittent for much of the trek, the hike’s summit was teeming with human activity. People congregated around the rescue crew and along the edges of the pool below.

A couple at the overlook asked my husband to snap a photo of them standing above the blue waters. As they posed, the man shared he had jumped into the pool with a wetsuit on his first visit and it it had hurt.

The hike’s popularity first ballooned in 2013, following the launch of Instagram several years earlier, according to The Oregonian. During the past decade, the natural gem has gained notoriety for both its beauty and its tragedies.

The pool’s water averages 37 degrees, which can cause immediate shock upon contact or hypothermia within 10 minutes of exposure. Some hikers have fallen from the cliff above the basin, while others have required rescue after cliff-diving adventures gone wrong.

A swimming ban will likely be put in place in the coming years, but an official ban needn’t be in place to stay safe by staying dry.

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More hiking tips

While visiting, take care to protect this popular spot for other visitors to enjoy for years to come. Practice the seven Leave No Trace principles, which include staying on the trail and packing out any litter or food waste.

The summer months are the busiest time on this trail, which is open year-round. Make plans to arrive early or on weekdays to avoid peak congestion.

The McKenzie River Trail stretches 26 miles through old-growth forests, lava fields and Douglas Firs. It can also be enjoyed from the 3-mile Waterfalls Loop Trail, with views of Sahalie and Koosah waterfalls, and Clear Lake Trail at the McKenzie River headwaters.

Nearby Tamolitch Falls: Waterfalls Loop Trail on the McKenzie River is a summertime treat for hikers

Getting there: From Bend, take Highway 97 north and exit at 135A to merge onto Highway 20 to Sisters. In Sisters, take the second exit roundabout to stay on Highway 20 for an additional 25 miles. Take the McKenzie Highway for about 10 miles then turn right at the sign for Trailbridge Campground/Blue Pool. Cross the bridge and turn right onto Forest Road 730 and continue to the trailhead.