Diablo Lake Washington: Camping and Hiking in the North Cascades

For pristine wildlife and scenery, it doesn’t get much better than the divine views of Diablo Lake in North Cascades National Park. North Cascades National Park is one of the lesser-visited but most stunning in the national park system, and Diablo Lake is an easily accessible attraction. Located 125 miles from Seattle, it’s worthy of a weekend trip (or longer if you can!) I often see appreciation for Canada’s Banff National Park and its beautiful landscape, but North Cascades National Park also offers expansive mountain views paired with turquoise-hued lakes without crossing the border.

The vibrantly-colored Diablo Lake is located in the Ross Lake Recreation Area within North Cascades National Park. Spectacular views and photos are readily available at North Cascades Highway 20 at the Diablo Lake Vista, but nothing beats the fun of getting your boots in the dirt and hiking it up close. For more information, go to the North Cascades Visitor Center.

trail sign

Hiking at Diablo Lake

There are several options for hiking views of Diablo Lake. During my two-night stay I tried two nearby trails. Such as:

Diablo Lake Trail

The Diablo Lake Trail starts at the North Cascades Environmental Learning Center and is about 7.5 miles out and back along Sourdough Mountain. The hike includes a handful of semi-steep climbs and offers views of the lake along the way, lakeside access, and an overlook of Ross Dam.

Thunder Knob Trail

The Thunder Knob Trail is a shorter, moderate, family-friendly hike at about 3.5 miles out and back. It leads through a creekbed, forest, and over a clear stream to an overlook on the south side of Diablo Lake with spectacular views of the surrounding peaks. 

colonial creek campground

Camping at Diablo Lake

To plan your stay, Diablo Lake camping can be done through drive-in, boat-in, or backpacking campsites. There are several options for drive-in campgrounds, but for those that allow campground reservations, you must book quickly in advance. During my August trip, I had luck finding a first-come, first-served RV spot at the Colonial Creek Campground thanks to the advice of a helpful park ranger.

If you’re traveling in the summer season without reservations, be sure to get to the park by mid-morning. Thanks to its proximity to Diablo Lake and trails and its boat launch, Colonial Creek Campground is a popular spot. My next trip will include a paddleboard so I can take advantage of the easy access to Diablo Lake with the other kayakers and canoers.

turquoise lake

An obvious draw to this memorable and photogenic landscape is the blue-green water color of Diablo Lake. Thanks to the crush of glaciers, rock sediment is ground into a ‘rock flour’ that feeds into Diablo Lake from glacial streams and is fine enough to be suspended in the water. The reflection of sunlight off the suspended particles in the lake creates a turquoise appearance. The lake is most vivid in spring and summer when it’s fed by more of the glacial melt. 

Skagit River Dams

Another noticeable, but unnatural feature of the landscape is the towering overhead powerlines visible from the trail. These powerlines are carrying electricity to Seattle thanks to the Skagit River dam system. Diablo Lake, and the nearby Ross Lake and Gorge Lake, are man-made reservoirs formed by the dam system.

The Diablo Dam portion was constructed in 1930. For decades, hydroelectricity created by water power harnessed through the dams has provided a significant source of electricity for Seattle. Experiencing the tranquility of Diablo Lake while knowing it’s helping power businesses, homes, and Zoom calls more than a hundred miles away was a striking way to appreciate the power of science and nature.

Editor’s Note: Interested in visiting the dams? You can drive across Diablo Dam to access the North Cascades Environmental Learning Center. Or hike the Ross Dam Trail and walk across Ross Dam for access to miles of backpacking trails and the Ross Lake Resort

diablo lake overlook
diablo lake
diablo lake

A Must Visit Gem

A trip to Diablo Lake Washington camping site or anywhere in North Cascades National Park can include a variety of other attractions and activities; including ferry boat rides, guided tours, educational programs, and more. (Many activities are currently canceled due to COVID restrictions.) But this gem is also perfect on its own as a simple weekend camping and hiking adventure. With its heavenly landscape, Diablo Lake is a must-experience.

Ron Morris


  1. Ron Morris on June 14, 2021 at 9:09 am

    Thank you for sharing! I’d love to hear more tips and favorite spots from others who’ve spent time at this incredible park. I’m already building my bucket list for my next trip back.

  2. Clark R Blomquist on June 14, 2021 at 5:12 pm

    Great idea. Coming to Washington this summer with our RV!

  3. TrevorG on June 21, 2021 at 10:08 am

    Isn’t Lake Ross the real destination??? Diablo is the lower smaller part.

    • lk on September 2, 2021 at 10:40 pm

      easier to get to/access diablo. ross lake requires portage, fees, and reservations at the singular resort + backcountry national park camping permits. yes, it’s huge and gorgeous, but requires more advanced planning.

  4. Charles on August 7, 2021 at 6:12 am

    It is actually Seattle only dedicated hydro power. The rest is from a nuclear plant owned by Energy Northwest.

  5. Choudoufu on August 10, 2021 at 8:03 pm

    I’m wondering how long the lake is. Is it big enough to spend a couple of days exploring by rowing skiff (~5mph cruising speed), or small enough to cover in half a day?

  6. Magali lopez on July 28, 2022 at 9:31 am

    Hello I want to make a reservation could you give me a number Please to camp in Diablo lake

  7. kimberly kalfas on September 3, 2022 at 1:45 pm

    Do I need a special pass of any kind if I am going to Colonial Creek Campground? Just making sure because I am leaving to go on Tuesaday.

    • June Evans on September 9, 2022 at 9:26 pm

      FYI-If you need a place to stay, while sight seeing in the North Cascade National Park. We Air B and B our cabin (Cozy Off-Grid Cabin, on Air B and B) its located in Marblemount. In a secure wilderness park, directly on the Cascade River.

  8. […] wildlife, rugged terrain and abundance of stops and trails to explore go, and go and go. The North Cascades captures adventure for everyone. From a big part of the Pacific Coast Trail (PCT), to even the […]

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