Trillium Lake Crag

Region: Mount Hood





Crag Beta

Trillium Lake Crag offers a handful of excellent quality routes both sport and trad in a quiet wooded setting with an easy, approach.


Finding the Crag


Directions from Trillium Lake: Day parking is not allowed at the campground but you can ask at the gate if there is an available spot. Otherwise, you will need to park along the access road and walk into the Northeast side of the lake. Locate the lake loop trail and the crag is hidden in the woods off the northeast tip. Find where the trail turns a sharp left at the north tip and east side. Follow a faint trail at this sharp turn and go north and up to the left side of the bluff. Don’t get sucked in by other undeveloped sections; look for bolts. 

0.3 mi

Walk Time
10-25 min

30-60 ft

  • Sport 60% 60%
  • Trad 40% 40%

GPS: 45.275832, -121.733874 

Type: Mostly sport 

Total Routes: 25

Also referred to as Mosquito Bluff, is a fantastic, small sport crag with a few trad routes. The area is located just above the pristine Trillium Lake. Gorgeous views of Mt Hood and the mirrored surface of the lake are just a few surprises you will find at this tranquil area. The crag is only a 5-minute walk from the campground. 

Camping is available at Trillium Lake right where you park to access the crag.

The Trillium Lake crag or Mosquito Bluff is a kid-friendly, dog-friendly crag.  The approach is level and easy to follow making it an easily accessible path to approach the crag.

Late spring to late autumn is best. Winter is  snowed in so climbing is not likely. The crag is cool in summer as it is in a shaded setting. The nearby lake has a great swimming area to cool off as well.

This crag is in National Forest and rock climbing and bouldering is allowed.  Please consult locals before replacing bolts or adding new routes.  Bolts were added recently and are in good condition as of 2020.

Walk along the east shore of the lake and continue straight. Where the trail veers right and left go left a bit and follow a faint path that goes north. If you end up in a marshy area you went too far to the left. You need to veer up the faint path to the bluff and the crag.


Bouldering at Mosquito Bluff and Trillium Lake can be found at a few spots on the bluff.  This is not a great bouldering area and there are only a handful of problems. The best problems are a few of the highballs near the shorter bolted routes on the south end of the bluff closest to where you walk in.  This is the rightmost part of the crag. If you walk along the bluff towards Route 26 where you drive in there are some low bouldering spots. The Bluff Cave has a steep but chossy overhanging face that was developed by Rob Holzman and has a route called The Contender that goes at V4.  Nothing else on this backside of the bluff is worth walking to.  Go to nearby Lost City to boulder instead, it is much better and larger than the limited potential here.


Local Guidebook

This area and other nearby Mt Hood crags are included in the Climb Portland, Mt Hood & The Gorge Print guidebook

Mosquito Bluff Photos

Trillium Lake Crags


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Nearby Crags


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