Obsidian Trail Backpacking Loop

12 mile loop
2,200 feet
Summer through fall
Central Cascades Overnight Permit, Northwest Forest Pass
The Obsidian trail is a lollipop loop on the west side of the Three Sisters in Central Oregon's cascades. Expect excellent mountain views of North and Middle Sister on this trail, and a beautiful bloom seasonal wildflowers. Explore the upper loop to find fields of obsidian, a waterfall, and a picturesque lake tucked away off-trail.

While doable as a longer day hike, I highly recommend the Obsidian trail for beginner backpackers or for more experienced backpackers looking for a relaxing night out. Read below for a detailed description, and for tips on how to find the secret lake!
Broken Top crater and trail #10 sign
Trail Map

Getting There and Parking

The Obsidian Trail is located off the McKenzie Highway, just below McKenzie Pass on the west side of the central cascades. If you're coming from Sisters, enjoy the scenic but narrow drive through McKenzie Pass, stopping at the Dee Wright Observatory for mountain and Belknap lava flow views.

Day and overnight visitors to the Obsidian trailhead are required to pre-purchase a Central Cascades Wilderness Permit. Find more information about permits in the section below.

Hike Details

For the first two to three miles, the trail gradually climbs uphill through a dense evergreen forest. As you climb, the forest begins to open up to meadows, and a rugged lava flow. If you're hiking in July, expect a varied wildflower bloom throughout the meadows.
After about 3.5 miles on the Obsidian Trail, you'll cross a small stream, arriving at the lollipop loop junction. Take a left at the fork to hike the loop clockwise, following signage for Glacier Way. Hike 0.8 miles on the The Glacier Way trail until it joins with the PCT, turning right on the PCT to continue the loop.
If you're backpacking, the best campsites are on the upper loop off the PCT. After roughly 0.5 miles along the PCT, you'll come to a user trail that veering left and crossing a stream (Glacier Creek). The wooded area beyond the stream has many amount of campsites along the user trail, and good access to water from the stream.
To find the lake, continue up the user trail, past the campsites in the trees. The trail will exit the trees into a rocky area, with a steep cliff on your right. F Follow the trail through the rocks for about 0.5 miles, then taking a sharp right to double back towards the cliff you say before. This path follows the sharp U-shaped line on the map above.
Once you find the small lake, soak in the views of Three Sisters mountains reflected on its glassy surface. There are numerous campsites scattered around the lake, so you may choose to camp here as well.
Hidden Lake
Flowers along the trail
To complete the loop, follow the PCT until it meets the Obsidian trail farther down. You'll pass Obsidian Falls and several more wildflower meadows on your way to the main trail. Once you've rejoined the main trail, it's 3.5 miles on a familiar route back to the parking lot.
Obsidian Falls

Permit Info

Day hikers and backpackers at the Obsidial Trail are required to carry a Overnight Permit or Day Use Ticket at all times in the Three Sisters wilderness. Permits must be purchased online prior to the date of your trip.

The Three Sisters permit season runs from June 15th to October 15th, becoming highly competitive during peak summer months. 40% of overnight permits are released on April 4th, at 7AM PDT , and another 60% are released on a 7-day rolling window from June through October. Day use permits are additionally released on 10-day and 2-day rolling windows, allowing the possibility of snagging a permit shortly before a day trip.

All permits are reservable on a first-come, first-served basis. To increase your odds of getting a permit, log into recreation.gov by 7AM the week before you want to backpack, and select your desired trailhead as soon as it becomes available. Permits sell out quickly for popular trailheads!

You may hike without a permit before June 15th or after October 15th, but please be prepared for the possibly of deep snow and difficult or dangerous weather conditions.
Bend Glacier close up

What to Pack



Goat Lake Campsite

Camp Kitchen

Oatmeal at Ramona Falls


Backpacking near Jade Lake in the Alpine Lakes Wilderness


Backpacking the Timberline Trail on Mt. Hood


Still have questions? Send me a message over email to connect. Happy Trails!
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Seven Lakes Basin High Divide Loop →

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About Us

Heart Rock at Joshua Tree
Thanks for visiting our travel blog, Trails And Trekking! We're Lauren and Anders - an adventure loving couple currently stationed in the Pacific Northwest. We're avid hikers, backpackers, and travelers. We're both originally from Oregon, but we've spent the last two years traveling the Pacific Northwest and beyond. We created this blog to share our passion for exploring the outdoors, and to inspire you to get outside.