Upper Thornton Lake and Trapper Peak

Getting There: Drive east on state Route 20 (North Cascades Highway) 11 miles past Marblemount and turn left on Thornton Creek Road. Drive five miles to the parking area to an elevation of 2,500 feet. The trail begins on an old logging road which you hike for a couple miles. The unofficial trail then goes into the forest on up to the ridge top (5,000ft). Views of Eldorado peak, Mount Triumph (7,270 feet), Trappers Peak (5,964ft) and Lower Thornton Lake. A beaten path down the otherside leads you to Lower Thornton Lake. Reach the middle and upper lakes by traversing slopes west of Lower Thornton Lake on a boot path to Middle Thornton Lake (4,700 ft). From this lake it is then necessary to scramble up a steep ravine/gully leading northwestward from the north end of the lake. The upper lake sets at 5,000 feet. This is the area you want to reach because the upper lakes and mountain views are incredible.

Location: North Cascades National Park
Trailhead: Thornton Lakes Trailhead
Elevation: Trailhead 2,500 ft , upper lake is around 5,000ft
Trail Length: 9.5 miles roundtrip to lower lake
Elevation Gain: 2,500 ft
Maps: Green Trails No. 47 Marblemount
Pictures: Lower Thornton Lake, Middle Thornton Lake, Upper Thornton Lake,
Closest Town: Marblemount

Forest Information:
Marblemount Ranger Station
North Cascade Highway
360-873-4590