The trail is hardly in "Eugene" Oregon, but starts in McKenzie Bridge Oregon, 60[!] miles upriver from Eugene, and ends at Clear Lake, the headwaters of the river. If you go, be sure and check out the "Blue Hole".
The McKenzie River Trail stretches around 25 miles through the majestic forests of the Cascade Mountains. It winds through spectacular waterfalls, lava fields and old-growth trees. Runners can lengthen or shorten their sprints by taking advantage of a shuttle service. The trail is also a favorite with mountain bikers, who have dubbed it the top trail in the nation.
For serious runners, McKenzie River Trail is also the location of the famous 50-mile race, which starts and finishes at the McKenzie River Ranger Station.