North Cascades National Park, Washington
On a summer road trip across Washington State, we decided it was time to explore one of America’s least-visited national parks: the North Cascades. The park sits high up in northern Washington State, almost at the Canadian border, and features its namesake, the Cascade Mountain Range. These mountains stretch between the States and Canada, and are considered the most rugged mountain range in the contiguous US.
Washington Pass Overlook
Alpine glaciers define the Cascade Range–from stratovolcanoes capped with glacial ice (i.e., famously, Mt. Baker) to non-volcanic glaciated peaks. The most famous of these, Mount Rainier, we would be visiting in just a few days.
From Spokane, Washington, we drove northwest into the Cascade Range to our first destination, an overlook to give us our first glimpse at the mountains. The Washington Pass Overlook sits at 5,500 ft. at a stop along the North Cascades Highway. From the parking lot, there’s a short paved path that leads right to the views.
From the viewpoint, we could see the 8,000-foot Liberty Bell peaks rising to the south. Seven hundred feet below us, we could see the road we had traveled zigzagging back and forth climbing up into the mountains.
Hairpin turns 700ft below us 
Lake Diablo
Following the North Cascades Highway west, we soon encountered our next, and perhaps most impressive, stop: the Lake Diablo Overlook. Lake Diablo is a reservoir created by the Diablo Dam and part of the Skagit River Hydroelectric Project system. In 2012, hydroelectric damgs, including those on the Skagit River, provided approximately 90% of Seattle’s electricity.
The lake gets its unreal turquoise coloring from surrounding glaciers that grind rocks into powders that creeks carry into the lake. That power (glacial flour) stays suspended in the lake, reacting light the light to bringing out the blue-green color. We had seen a similar phenomenon in New Zealand when we explored glacial-fed lakes in the South Island.
Thunder Knob Trail
Lucky for us, there is tons of fantastic hiking around the lake and in the North Cascades generally. We chose a relatively easy hike on Diablo Lake, the Thunder Knob trail, a 3.5 mile roundtrip.
The hike starts at a campground. Since we were visiting during the summer, there were tons of people hanging out around their tents, paddling around the lake, swimming, and fishing. Diablo Lake is full of rainbow trout. For the first mile or so, the trail climbs through a verdant forest, with mossy carpets, decaying logs, and bright ferns. It had very strong Washington State vibes. There are a few viewpoints along the way, and then a marsh to cross.
At the top of the trail, at Thunder Knob, we could see Diablo Lake and the dam in the distance. At the time it was built in 1939, Diablo Dam was the highest dam in the world (389 feet).
