Olallie Trail stretches for nearly 10 miles along a massive ridge that runs between the Three Sisters and the East Fork of the South McKenzie River. The trail alternates from one side of the ridge to the other, offering unbroken views of the Cascades as well as glimpses into the steep river valley to the west. The descent back down to the trailhead parking lot is one of the fastest singletrack downhills anywhere. If you have the desire, it is not hard to hit 30 mph on this 10-inch wide ribbon of dirt.
It is possible to ride Olallie as a straight out and back, but utilizing the adjacent paved Forest Service Road 1993 to access the middle trailhead at Horsepasture Meadow will make this already grueling ride slightly more pleasurable. The road also offers spectacular views of the Cascades from the Three Sisters to Mount Hood on a clear day. NF-1993 is currently blocked by a large landslide about 1 mile past the northern trailhead, making it impossible to shuttle a car to the top of the ridge. You will have to scramble across logs and boulders for about 500 feet to regain the road.
From the trailhead at Horsepasture Meadow, head south on Olallie Trail for about 5 miles. This portion of the trail is poorly maintained, so expect some overgrown sections. Turn around at the end of a section of beargrass, just before the trail descends steeply back to road 1993. Once you make it back to Horsepasture Meadow, another mile of climbing through more spectacular views leads to the O'Leary Mountain Trail junction and the beginning of the downhill. From here it is 4 miles of smooth, high-speed singletrack descent,with a few widely spaced switchbacks near the bottom. Don't push your limits; while the trail is smooth, it clings precariously to the side of a steep hillside. A crash at speed here would likely result in serious injury.
This is a physically demanding wilderness ride, with the road accessible at only a few points. Bring tools, a map, and plenty of food and water.