The Olympic Peninsula loop feels like a trip by the first evening, with the rig backed in along the shore of Lake Crescent and the water going flat and dark under the ridges. A few nights on, you're parked on the bluff at Kalaloch with the Pacific working at the driftwood below, and in between is the Hoh, where moss hangs off the maples in sheets and the light comes through green. It's the week Washington families keep coming back to, a lap of Highway 101 around Olympic National Park with a night on the lake, a night in the rain forest and a night on the beach.
Past the peninsula, the state's RV trips run in three more directions. The coast road south and the long road east make Seattle the top of a one-way run, SR-20 climbs through the North Cascades to the dry side, and a hookup base at the foot of Mount St. Helens sets up a parked week under the volcanoes.
The Olympic Peninsula loop on Highway 101
Clockwise from Port Angeles, the first night belongs to Lake Crescent. Log Cabin Resort, on the lake, has full hookups for rigs up to 35 feet and takes reservations by phone. Fill the fresh tank and empty everything there, because the rest of the loop runs on park campgrounds.
From the lake, 101 swings west toward Forks, and the second night is Mora, in the forest near the sea stacks of Rialto Beach. Night three is the Hoh, where the rain-forest trails start at the campground and the river runs milky with glacier silt past the sites. Then the road comes back to the ocean at Kalaloch for the last beach night before the run south past Lake Quinault and home.
Lock the campsite before you book the rig. Only a few sites at Mora, the Hoh and Kalaloch take a motorhome up to 35 feet, per the Park Service as of September 2026, so the pad you get decides the class you rent. The Hoh has no dump station, which is why Mora comes first: empty there on the way in and again at Kalaloch on the way out. Fairholme, at the west end of Lake Crescent, is the dry fallback to Log Cabin, with a dump station and some sites to 35 feet.
If those longer sites are already gone, or it's two of you heading for the La Push and Kalaloch beaches, the Washington campervan page has that coast week in a smaller rig. For the loop night by night, with the hookup towns along 101 between the park nights, the Seattle RV page has the full run.
One way from Seattle, down the coast or east to Salt Lake City
The long version of the coast trip keeps going. It leaves Puget Sound for Highway 101 and follows the Pacific south through Oregon, with beach nights stacking up until the redwoods and then San Francisco or Los Angeles. The eastern run crosses the Cascades and the dry side of the state and carries on across the interior to Salt Lake City.
The Seattle RV page maps both corridors and the nights along them. The rig is returned at the far end: Cruise America offers one-way rentals from its Seattle center in Everett.
The North Cascades Highway, SR-20 to Winthrop
SR-20 climbs out of the Skagit valley into a gorge where the river runs in the rock below the road, then opens onto Diablo Lake and Ross Lake, their water gone glacier-green between the dams. The first night is in the park at Newhalem or at Colonial Creek on Diablo's shore. The next morning the highway goes over Washington Pass and drops into the Methow and the Old West storefronts of Winthrop.
Pearrygin Lake State Park, just outside town, is the dry-side night, a spring-fed lake with shrub-steppe hills all the way around. The park campgrounds along SR-20 book on Recreation.gov, and Pearrygin has a trailer dump for emptying after the nights in the park. SR-20 over the passes is a seasonal road, so check WSDOT's pass report before you lock the loop. The Everett RV page runs it from start to finish.
South of the Methow, Lake Chelan State Park is a summer habit, with families returning to the same shore every year and sites that need booking early. Farther into the coulees, Sun Lakes-Dry Falls State Park has full-hookup sites up to 65 feet, with limited availability, for a parked week under the basalt walls below Dry Falls. The lakes farther east belong to the Spokane RV page.
Mount St. Helens and Rainier from Seaquest State Park
Mount St. Helens still looks like the mountain that blew, its north side gone and the valley below the crater a pale plain of pumice where the forest used to stand. Seaquest State Park, in the trees across from Silver Lake at the start of the road up, makes a week-long base for it. The T-loop has full-hookup sites, room for rigs up to 50 feet in limited spots, and a dump station.
Mount Rainier is the other big day out, and the Tacoma RV page covers both mountains with a base outside the park gate. Inside Rainier, plan the tanks around the Cougar Rock dump station, which is closed until further notice as of September 2026.