Thornton Lake Trail

  • Thornton Lake in North Cascades National Park.
  • Thornton Lake in North Cascades National Park.


Dogs No


10.4 (miles)


Out & Back

~2900 (+) (Elev. Δ - ft)


The Thornton Lake Trail in North Cascades National Park is a truly fantastic wilderness experience. The hike is a challenging day hike or also makes a great overnight backpacking trip. The hike initially follows an old logging road built before the park was established. This area can be quite bushy, but is filling in nicely after being logged with Douglas Fir, Mountain Hemlock, Pacific Silver Fir and more. Next up comes steep switchbacks that will build character! Along the way hikers can expect fantastic views of Mt. Triumph, Teebone Ridge, and the Skagit Valley. A scramble up the spine of Trappers Peak leads to sweeping views of all three lakes and stunning alpine scenery. Once hikers reach Thornton Lake they are greeted with world-class views. The classic cirque lakes were created by glaciers scouring the land, then retreating. A primitive climbers path leads to other lakes nearby. Wildlife is abundant near Thornton Lake; watch out for raptors, marmots, deer and yes bears. You are in the heart of bear country here, so please be bear aware There is plenty of camping in North Cascades National Park.

Red Tape

Entrance and Camping Fees Backcountry permits are required, but free.
Contact: North Cascades National Park Service Complex 810 State Route 20 Sedro-Woolley, WA 98284

Washington Trails


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