Diablo Lake

Book a boat tour through the deep gorge of stunning Diablo Lake in Washington State.

Diablo Lake is 2.5 hours drive from Seattle along State Route 20 in the North Cascades (check highway closures in winter). The nearest towns are Marblemount and Newhalem.

This gorgeous lake is surrounded by vertical walls of solid granite, and jagged, snowcapped peaks. The stunning turquoise water is caused by run-off from a fine powder found in glacial melt.

This area was originally a gorge, flooded in 1930 after the construction of the Diablo Dam created this 5-mile long reservoir.

Book a ticket for the popular 2 to 3 hour boat tour of Diablo Lake, or stay overnight at the North Cascade Environmental Center.  Go kayaking on the pristine waters, explore trails with incredible viewpoints, and stay at a choice of four campgrounds. Swimming is not recommended at Diablo Lake becaue the water temperature is usually below 50 degrees.

10 best things to do at Diablo Lake

1. Take a thrilling drive across the 389-foot Diablo Dam!

To get to Diablo Dam, drive roughly 7-miles east of Newhalem on State Route 20, then take the turnoff to the North Cascades Environmental Learning Centre. Drive down the hill and then across the 389-foot Diablo Dam, before ending at the North Cascades Environmental Learning Center.

The Diablo Dam was constructed between 1927 to 1930, to supply Seattle with electricity, and was once the tallest dam in the world. 

The Diablo Dam is part of the Skagit River Hydroelectric Project, where a series of three hydroelectric dams were built along the Skagit River in the 1920s and 1930s to generate 20% of Seattle's electricity.  The three dams running from east to west, are Ross Dam, Diablo Dam and Gorge Dam.

2. Book a boat tour of Diablo Lake with Skagit Tours.

The Diablo Lake Boat Tour is only available in summer months, and advance bookings are required. There's both a morning tour with lunch, and an afternoon tour to choose from.

The boat tours start at the rustic North Cascades Institute Environmental Learning Center on the shores of Diablo Lake.

The Learning Center has picturesque walking trails, a restroom and gift shop, and lunch is included with some of the tours.

A Park Ranger provides a few instructions, before this group sets off on a fun boat cruise of Diablo Lake.

The talk is held around a campfire, just outside the Learning Center at Diablo Lake.

The group then follows the Park Ranger down to the boat dock at Diablo Lake.

The boat dock is now visible at Diablo Lake. 

The friendly Park Ranger provides a few more instructions, before the group waits to board.

Everyone waits patiently for the boat to arrive.

Finally the boat arrives, and is ready for boarding!  This is the Alice Ross III (now replaced by a new boat, the Alice Ross VI).

Here's the boat captain for the Diablo Lake tour.

There's lots of space above deck to take photos.

The boat travels across Diablo Lake, past two enchanting islands. The tour is narrated by both a Park Ranger and Naturalist, providing a fascinating insight into the rich history of the lake. 

The first public boat tour of Diablo Lake was offered in 1927 to visitors from Seattle, and became immensely popular due to the efforts of pioneer J.D.Ross.  He was the father and early superintendent of the Skagit Hydro-electricity project. J.D.Ross staged elaborate boat tours to impress visitors, featuring classical music, surprises hidden on the islands, and even an island populated with monkeys!

The boat then enters a deep, rugged gorge on Diablo Lake, offering a glimpse of true wilderness. 

It's lush and secluded in the gorge, full of ferns, moss, and evergreens clinging to rocks.

A smaller waterfall becomes visible, cascading into the turquoise waters of Lake Diablo.

The magnificent John Pierce Falls soon come into view, named after a construction worker who fell from the highway above to the falls below, but miraculously survived!  There's actually a hike that crosses this bridge, so you can see the falls from another angle.

Here's a close up view of the John Pierce Falls at Diablo Lake.

After a brief glimpse of the Ross Lake Dam at the east end of Diablo Lake, the boat turns around and retraces its path back to the boat launch.

Remote Ross Lake is also part of the Skagit Hydroelectricity Project comprising Diablo, Ross and Gorge Lakes, and home to the incredibly remote Ross Lake Resort inaccessible by road. The waterfront cabins at Ross Lake are booked out a year in advance, and can be reached by hiking in.

Diablo Dam comes back into view on the way back to the Environmental Learning Center.

Finally some blue sky on Diablo Lake!  After leaving the boat tour, visitors are free to explore the gift shop and trails at the North Cascades Environmental Learning Center.

3. Stay overnight at the North Cascades Environmental Learning Center at Lake Diablo.

The North Cascades Environmental Learning Center has some exciting packages for overnight stays, with meals and lodging included. 

The Family Stays include guided hikes, canoe trips, outdoor games, arts and crafts, fireside storytelling and night-time walks.  What an incredible experience for kids! There's also Base Camp packages for adults with guided tours and naturalist talks.  Learn more about bookings.

5. Explore more challenging hikes near Diablo Lake in the North Cascades.

There are so many great hikes around this area with stunning views of Diablo Lake, but you need to be properly prepared.

Hikers should first stop at the North Cascade National Park Wilderness Information Center at Marblemount for information on weather conditions, maps, and back-country permits (7280 Ranger Station Road, Marblemount, off State Route 20).  This information center is closed in winter, but they can be contacted by email.

6. Go kayaking on the turquoise waters of Diablo Lake.

Launch your kayaks from the pretty Colonial Creek Campground at Diablo Lake, just off State Route 20.  See all the same sights as the boat tour, and paddle 5-miles up to Ross Dam. It can get windy out on the lake, so always wear a life-jacket. 

Unfortunately there are no kayak rentals at Diablo Lake.

7. Stay at a drive-in campsite on Diablo Lake.

The only drive-in campground at Diablo Lake is Colonial Creek Campground.  It's very easy to get to, with campsites directly off State Route 20.  Camp near the water's edge surrounded by old growth forest, with a fishing pier, boat launch, seasonal vault toilets, but no showers. Make a reservation.

8. Obtain a permit for a boat-in campsite on Diablo Lake.

There are 3 boat-in campsites at Diablo Lake that can be accessed from the boat launch at the Colonial Creek Campground. They are the Buster Brown, Hidden Cove, and Thunder Point campgrounds, roughly 2 to 2.8 miles from the Colonial Creek Campground.  Back-country permits must be obtained from the Wilderness Information Center at Marblemount to camp at these boat-in sites.  The Wilderness Information Center is closed in winter, but you can contact them on email.

9. Drive back up to the highway to the Diablo Lake Vista Point for an amazing photo opportunity.

The Diablo Lake Overlook is 11-miles east of Newhalem on State Route 20, with gorgeous views over Diablo Lake to Diamond Peak.

10. Stay overnight in nearby Marblemount or Winthrop.

The North Cascades Inn is 30 minutes west of Diablo Lake at the tiny township of Marblemount. 

The fun, western-themed township of Winthrop is another 1 hour and 15 minutes along the highway, and has a big selection of accommodation in a sunny, riverside setting.  Enjoy a meal on a patio beside the river while listening to music.