Split into North and South units along Diablo Lake’s striking turquoise water, Colonial Creek is the most popular and centrally located campground in North Cascades National Park. Sites offer vault toilets and potable water, no hookups, and the campground’s lakeside setting means kayaking and canoeing right from camp, along with easy access to the Thunder Knob Trail. Given North Cascades sees far fewer visitors than nearby Mount Rainier or Olympic, even this popular campground tends to feel less crowded than comparable spots in busier parks — though summer weekends still fill given the limited overall camping capacity in this park. The North Cascades Highway through the park closes each winter, making this a firmly seasonal (roughly May through October) destination.