Middle Sister is the middle and shortest of a series of 3 volcanic peaks rising just over 10,000 ft. in the Cascades of Central Oregon west of Bend. The easiest route is the North Ridge Route which is accessed via Hayden Glacier on the east side and Collier or Renfrew Glaciers on the west side. These routes are easy glacier slogs to a saddle between North and Middle Sister. The North ridge is then a walk up a snow, cinder and small rock hopping ridge.
Pole Creek trailhead (for the east side approach): travel 1.5 miles west of Sisters, OR on Hwy 242, turn south on Forest Service road 15 which is paved at first, but the pavement soon yields to trademark Central Oregon washboard gravel. Follow the road for 7.1 miles, where you'll reach a "Y" intersection. Stay left at the junction (following the signs to Pole Creek), and follow the road to its end just past milepost 10 at the parking area for the Pole Creek Trailhead.
Obsidian Trailhead: (for the west side approach): this trail head is located approximately 4 miles west of McKenzie Pass on Hwy 242.
Free Wilderness Permits are required for all entry into the Three Sisters Wilderness from Memorial Day to October 15. These can be obtained at self serve kiosks at the trail head or at ranger stations. A Trail Pass Parking Permit is required to park at or near all trailheads. These are $5 for single use or $30 for an annual pass. They can purchased at ranger stations, at an Iron ranger on FS Rd 15, from various other sites around the area, or via phone 1-800-270-7504.
Additionally the Obsidian Area has a limited entry permit (20 people per day) and may only be obtained at the McKenzie Ranger Station Office.The permit may be obtained up to 30 days prior to use. Permits may be obtained via phone, mail, or in person.
McKenzie Ranger District
57600 McKenzie Highway
McKenzie Bridge, OR 97413 (541) 822 - 3381
There are camping and campfire setbacks in certain areas of the Three Sisters Wilderness. Check with rangers.
The mountain is climbed year round. Winter has a long ski or snow shoe approach but provides a wonderful alpine experience. Most people summit during the summer when, depending on the route chosen, one may not even step on any snow.
Camping is allowed in the area and on the mountain. Check on special restrictions and special setbacks with the ranger offices.