Thornton Lakes & Trappers Peak

getting there

Drive SR-20 to 11 miles east of Marblemount and turn north onto Thornton Lakes Road. Continue to the road's end and trailhead (2,600 ft).

on the trail

Hike the Thornton Lakes Trail climbing through forest to a ridge crest at 5,000 ft with views down to the Thornton Lakes and across to Mount Triumph.    The lakes can be reached by poor trail down 500 feet from the ridge, about 1.5 miles to the farthest upper lake.  But for the most stunning views, from the ridge crest follow a climber's track up the ridge to the summit of Trappers Peak, about 1.5 miles and 950 feet farther up.

• Thornton Lakes: 10.2 miles round trip with 2,900 feet of elevation gain to a high point of 5,000 ft
• Trappers Peak: 10.6 miles round trip with 3,300 feet of elevation gain to a high point of 5,964 ft
• Thornton Lakes & Trappers Peak: 13.6 miles round trip with 3,800 feet of elevation gain to a high point of 5,964 ft

notes

• In some places the final section to the summit requires the use of hands, though not particularly difficult or exposed unless dangerous snow patches are present which they can be early in the season.  If you don't like the looks of the last section to the summit, extraordinary views can still be had partway up.

information for leaders

Courses, paid clinics, staff-led programs, and course field trips require a Commercial Use Authorization. The Park typically accepts applications for 2-year CUAs  through mid-March each year, and CUA's are activity-specific. Please contact info@mountaineers.org if you would like to apply for a CUA for a field trip or paid clinic for an activity we do not already have a CUA for. Please follow all Mountaineers group guidelines when leading trips or courses in North Cascades National Park. 

Notes:

• Leaders are responsible for securing backcountry permits or other required permits even if  we have a CUA.
• Leaders must have all relevant CUAs with them in paper or electronic copy to show Parks Staff as requested. 
• All Hiking course field trips or paid clinics must have a First aid and CPR certified leader. Current (non-expired) certificates must be uploaded to the park web portal by Mountaineers staff prior to the trip
• All mountaineering field trips or paid clinics must have a WFR-certified leader and a leader with documented climbing certifications (an AMGA certification OR Mountaineers climb leader with a recent resume of training and experience). Both qualifications must be uploaded to the park web portal by Mountaineers staff prior to the trip

View list of current North Cascades CUAs

• Suitable Activities: Day Hiking, Scrambling
• Seasons: July, August, September, October
• Weather: View weather forecast

• Difficulty: Very Strenuous
• Length: 10.6 mi
• Elevation Gain: 3,300 ft
• High Point: 5,964 ft

• Land Manager: North Cascades National Park
  Ross Lake National Recreation Area
• Parking Permit Required: None
• Recommended Party Size: 12
• Maximum Party Size: 12
• Maximum Route/Place Capacity: 12