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Flattop Flyer

 4.5 (4)
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10.4 Miles 16.8 Kilometers



1,631' 497 m


-1,636' -499 m



Avg Grade (3°)


Max Grade (12°)

2,122' 647 m


497' 152 m


Shared By Will Corbridge



Getting forecast...

Mostly singletrack downhill with 2-car shuttle; can be done as and out and back.

Will Corbridge

Dogs Unknown

Features -none-

Pretty muddy in the fall and the spring - ride your fatbike or wait it out. Can be ridden in the winter once it's snowy.


A fun, long downhill if you have a 2-car shuttle. You can also start at the bottom and ride up then back down if you want to earn it. The upper singletrack section has nice views along the canyon that becomes Powerline Pass at higher elevation; the lower singletrack section is Hillside Park .

Need to Know

Put a bell on your bike - high bear activity in the summer, lots of moose year round, and when you're bombing downhill you'll want to alert uphill traffic.

For the two-car shuttle, park one car at the Glen Alps (flatttop) parking lot (this is the uphill end) and the other at the Hillside Park parking lot (this is the downhill end). Can also do a shorter version with the downhill car at the Prospect Heights parking lot instead of Hillside. Prospect Heights and Glen Alps require either a State park pass or a $5 fee.

It's worth repeating that the upper singletrack section gets muddy in the spring and fall, and parts of it stay muddy year round. Be okay with getting dirty.


Starting out the Glen Alps parking lot, head out to the Powerline trail and turn left. Riding down the powerline is a wide-open doubletrack trail. You'll generally be bearing right off the powerline trail then snaking back towards it on this ride - bear right and head in a generally downhill direction.

Ride past Blueberry Hollow (hiking only) to South Rim Trail. Turn right here. The trail heads east to start and then quickly bears left. Ignore a couple of left turns and bear right as you head downhill with the valley on your right. Go straight through the intersection with Golden Grass Trail, then straight through Powerline Pass. Shortly after crossing the Powerline, the trail will put you on the driveway for the Prospect Heights parking lot/trailhead for a short period (if your downhill car is at Prospect Heights, you're done).

Turn right off the Prospect Heights driveway just before it joins the paved road - this is the Gasline trail, which is a brief, wide open section before you join the Hillside Park singletrack trails for the rest of your ride down. The quickest downhill progression via Hillside Park is to take Janice's Jive from the Gasline, then bear left onto Queen Bee Loop, then Drone Lane .

If you ride up before riding down, some people prefer to ride straight up the Powerline Pass trail and bypass the upper portion of the singletrack. This is a bit quicker and more direct, but not quite as interesting or technical (you'll still hit the interesting/technical stuff on the way back down). For this GPS track we rode up the powerline to cut out part of the South Rim Trail and Blueberry Hollow section.


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Your Check-Ins


Aug 26, 2018
Ray Burns
May 27, 2018
S.G. Thompson
Jul 6, 2017
Phillip Tr
certain section is very muddy. saw some moose and bear poop on the trail. 10.8mi
Jun 16, 2017
Phillip Tr
You can leave your car at flattop and bike all the way home to pick up your other car. The trail connects to the green trails of Campbell creek an...
Jul 20, 2016
David Donaldson
Be bear aware. Tall grass hides the critters very well on the South Rim portion of the trail.

Trail Ratings

  4.5 from 4 votes


  4.5 from 4 votes
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