0.8 mi of trail, end to end · 200 ft of descent · 1,287 ft–1,486 ft · native material surface · trail No. 574 · trail class 3 · typical grade 12-20% · tread 18-24 inches wide
TrailheadAlder Flat Trailhead 1,489 ft Drive there
Alder Flat Trailhead the Forest Service's write-up
No fees.
Trailhead for Alder Flat Trail #574 . Parking area has space for 4-5 vehicles with limited overflow
Restrictions See <a href="https://myodfw.com/fishing/willamette-zone">Oregon fishing regulations</a> for specific regulations governing fishing in the Clackamas River. <a href="https://myodfw.com/recreation-report/fishing-report/willamette-zone">Visit the Willamette Zone recreation report here.</a>
The lines are the US Forest Service's National Forest System trails layer (public domain), read 2026-10-16 and simplified for the map; the length is the line's, end to end, and the class, surface, grade and tread width are the forest's own entries where it publishes them - a forest that publishes the centreline alone has none. The trailheads and the points along the way are the Service's recreation points, and the write-ups its own recarea text, unedited. Heights come from USGS 3DEP through Terrain Tiles on AWS (Mapzen/Tilezen), read along each line and rounded; a short trail on steep ground can be off by a few tens of feet. Closures change: check the forest's own site before you go.
