Distance: ~11 Miles
Elevation Gain: ~2,800 feet
Best Time of Year: All-year round!
With the exception of the Wildwood End-to-End, the North Nasty is perhaps the most discussed route in Forest Park. Its steep climbs and close proximity to town make it the perfect four-season training ground for aspiring mountain runners. In the wet season, this route can be a truly "nasty" mud pit, but that's half the fun. Escape the crowds and explore the "quiet side of the park" on this classic Forest Park route.
Trailhead: Leif Erickson TH at Germantown
This route passes by several different trailheads. Therefore, you could conceivably park and start from any trailhead on the North Nasty. Be warned, car break-ins are a risk at all trailheads in Forest Park. Practice good habits and do not leave ANYTHING in your car.
Begin by entering through the gate for Firelane 9 on the North side of Germantown road. You will descend down to another gate, taking a right on an access road and then a sharp left on NW Wilark Ave into the neighborhood. Follow this road until it ends and there is a stairway on your right that takes you down to a raised walkway above highway 30. Take a left at the bottom of the stairs and head for Linnton Trailhead.
Linnton Trail starts with a gentle climb along the creek before crossing a footbridge and beginning to steepen. This is the first of the two biggest climbs on the route. As you ascend the switchbacks of Linnton trail, thick tree roots cover the trail and sword ferns line its flanks. In my opinion, this is one of the most underrated trails in the park. It has a much more wild vibe than most of the trails on the Southend of the park while still maintaining great trail conditions.
Continue the long climb up Linnton trail until you intersect Firelane 10. Stay straight and continue climbing. As the climbing begins to mellow out you will continue straight when you pass the Wildwood trail junction until you reach Newton parking lot. From the parking lot, continue straight across the lot. This is the start of Newton road. Continue on this old road bed, passing by another junction with Wildwood trail before it begins a steep rocky descent. You will follow this trail down and around the hillside, crossing Newton creek.
Continue on the trail along the creek until the trail veers left, paralleling the highway below. Beginning in this section, beware of poison oak. In recent years, poison oak has begun to pop up in this area, specifically in the unshaded section right before you intersect BPA road.
Take a left on BPA road, a powerline road easement and our stoutest climb of the day. Again, beware of trailside poison oak on this lower section, of which there is lots. This climb, although tough, is packed with wildflowers in the spring and berries in the summer. It also offers unbelievable views of the Willamette and Columbia rivers, Sauvie Island, and, on a clear day, Cascade volcanos to the North.
As you reach the top of BPA road, you can continue on the route, or make a short detour to the picnic tables at the top of the hill (right beneath the powerline pylons) via Firelane 13 on your right, remembering to return back to BPA to continue your route.
Continue on this upper, rolling section of BPA until you reach the turn for Firelane 12 on your right. You will take this turn down until you reach Firelane 15 on your left and begin climbing up Firelane 15. Firelane 15 will continue to climb, passing another junction with the Wildwood trail. Continue up and the climb will relent. This is the start of a more rolling section of Firelane 15. Continue past Kielhorn Meadows trail (this trail is a dead end) and pop out beneath the powerlines once again.
From here you will descend then climb, then descend and then climb until you've reached Skyline Boulevard at the terminus of Firelane 15. You will turn left on Skyline, running along the road for a short bit. There is one blind corner on this road, but for the most part, running along this section of Skyline feels pretty safe.
As you continue on this road you will eventually hit the unassuming BPA parking on your left. It would be easy to miss if you were unfamiliar, so keep your eyes peeled. You will head through the gate and continue on this upper portion of BPA heading down to Wildwood trail. This junction can be a little confusing for some. You will first pass Wildwood trail on your left (continue past this) and then about a hundred feet later you will see Wildwood trail on your right. Take this right turn and hop onto wildwood for some nice rolling miles.
This will take us all the way back to the junction with Newton road, but we will continue on Wildwood trail until we hit Firelane 10. Take a left on Firelane 10 and make the steep descent back down the climb we did earlier. This time, be sure to make the sharp, winding right turn to continue on Firelane 10 when you hit Linnton trail. This will take you down to a creek crossing and then one more punchy climb back up to Germantown road. Take a left once you have popped out at Germantown and carefully cross the road back to your parked car.