Basic Backpacking Field Trip

Field trip: Basic Backpacking

Basic Backpacking Field Trip - Thunder Creek

Thunder Creek overnight field trip for the Basic Backpacking Course. This is the last scheduled activity for the course.

COVID-19: Learn about our most up-to-date guidance for participants and leaders on our COVID-19 Response page. All participants and leaders must agree to the COVID-19 Code of Conduct before participating in this Mountaineers activity.
  • Easy
  • Easy
  • Mileage: 11.0 mi
  • Elevation Gain: 1,200 ft
  • Pace: 1 - 1.5 MI / HR


Meet 9:30am Thunder Creek trailhead parking area at far end (curved section of Colonial Creek campground road, ready to backpack by 9:45am. 

Trailhead parking directions:  Drive through the first big campground parking lot via the one-way road (on left) to the smaller parking area at far end (curved road section) of campground to Thunder Creek trailhead.

Directions to Colonial Creek CG:  Drive I-5 north, take exit 230 in Burlington for State Route 20 (SR-20, North Cascades Hwy).  Travel east on SR-20 through Sedro-Woolley, Marblemount, Newhalem.   Colonial Creek CG is 25 miles east of Marblemount.   Turnoff for CG is on right, south side of SR-20 near mile marker 130.

Estimated driving time 3-4 hours:  Seattle/I-5 north to Burlington/SR-20 1.5-2 hours (approx 70 miles) and Burlington to Colonial Creek CG 1.5-2 hours.  Total estimate 3-3.5 hours north and 3-4 hours south.


About Basic Backpacking Field Trips

The Basic Backpacking Field Trip, or "student backpack", is the final scheduled activity of the Basic Backpacking Course.   For most students it will be their first overnight trip in the backcountry.  Student backpacks are usually single-night trips along Easy or Moderate routes that do not present any unusual technical challenges.   

Covid-19--We will follow all Mountaineers Protocol--each participant is to bring a cloth facemask and hand sanitizer.  The mask must to worn when within 6' of others. 

Our one-night backpack in the Thunder Creek valley is 11 miles round trip with 650' gain, with a leisurely to moderate pace.   This is one of the best forest trails in the North Cascades and with a long hiking season, offering connections  to loop and one-way backpacks into North Cascades high country. 

The trail begins at 1,200 feet with a .8 mile contour along west side of Diablo Lake's Thunder Arm.  At 1.4 miles, you will cross a bridge over Thunder Creek and continue upstream along its east side.  Continue straight through a junction (left trail to Fourth of July Pass) at 2.1 miles.  Trail  varies from level to gentle rolling stretches, mostly within lush old-growth forest except for a couple old fire openings at 4.5 and 5 miles, where you see the summits of Snowfield and Colonial peaks.  Our McCallister stock campsite at 5.5 miles is the former site  of the Middle Cabin.  We'll aim to return to the trailhead, early to mid-afternoon on the following day.

Enjoy abundant varieties of blooming late spring wildflowers.  See and hear bird sounds and perhaps glimpses of other forest wildlife.    Leader is knowledgeable about many of the wildflowers, lichens and birds along Thunder Creek, and will help identify for interested participants.  

McCallister stock backcountry group camp (holds 8-10 tents) reserved for 6/12.  2021 Update: The new McAllister Camp is now open! It is located on the same side of Thunder Creek as the trail and is currently accessed via the McAllister stock camp.

Backcountry camp reservation  fee $20 paid by leader.  Please bring cash ($3-$5/each) to share cost with leader and participants.   No trailhead parking fees or passes required.

Facilities include pit toilet and creek water source near camp.   Bring Ursack, bearproof food canister, or food  hang bag (with 50' rope) for food storage.  Camp water source is a side creek, located about 5 minutes from camp via the main hiking trail.

5/31 conditions: trail is cleared of downed trees to McAllister camp. Heavy blowdown and many downed trees beyond (where we will not travel).  Trail is melted out to McCallister camp and about 7 miles beyond.  

Green Trails map:  Diablo Dam (No. 48).  Covers entire backpack trail.

Cameras are welcome.  The leader will be bringing a camera to photograph a few flowers, old-growth forest and mountain views.

NOTE:  Participants can drive to trailhead early morning prior to the backpack, or may choose to drive up a day early and car camp evening prior at Colonial Creek CG or other park campgrounds along hwy 20.  As of 5/14, no park campsites available for 6/11.  Limited motel space for Friday night may be available between Burlington and Marblemount.

The backpack leader will be staying overnight Friday in Marblemount and driving to trailhead Sat AM.

Looking forward to joining you on the Thunder Creek backpack !


Thunder Creek

  • Green Trails Diablo Dam No. 48

    Green Trails Mt Logan No. 49

    Green Trails McGregor Mtn No. 81

    Trails Illustrated North Cascades National Park
  • See full route/place details.
Required Equipment

Required Equipment

See course lectures and handouts.

Trip Reports