Montana

Glacier's largest campground sits at the foot of Lake McDonald with 194 sites spread across loops in a cedar-hemlock forest. Apgar is the west-side basecamp for Going-to-the-Sun Road, the Lake McDonald boat shuttle, and the Apgar Village amenities (general store, restaurant, ranger station). Most loops accept reservations through Recreation.gov six months out and book solid for July and August within minutes; a small first-come block fills by mid-morning in summer. Lake McDonald's polychromatic pebbles at the campground beach are one of the most photographed shorelines in the park.

If Glacier has a single must-camp, it's Many Glacier. The 109-site campground sits beneath Mt. Grinnell in a glacier-carved valley most visitors only see from a tour bus, with the Grinnell Glacier, Iceberg Lake, and Cracker Lake trailheads all within walking distance. Grizzly activity is high — bear-resistant food storage is mandatory and routinely inspected. Reserve six months out the moment the booking window opens; the entire summer typically books within an hour. Loops B and C accommodate RVs up to 35 feet.

Glacier's east-entrance campground sits in cottonwoods along the St. Mary River with 148 sites, an amphitheater, and the most wide-open sky in the park. St. Mary catches morning light on the Lewis Range east face and is the closest campground to the eastern Going-to-the-Sun gateway and the Two Medicine and Many Glacier turnoffs. Wind off the plains can be ferocious — stake everything down. Reserve through Recreation.gov; loops open progressively from late May through mid-June depending on snowmelt.

The most under-appreciated corner of Glacier. Two Medicine's 100 sites sit beside the lake of the same name in Glacier's southeast, where the Blackfeet Nation borders the park and crowds drop to a fraction of Many Glacier or Lake McDonald. The Dawson-Pitamakan loop, Sinopah, and the boat-assisted hike to Twin Falls all start from camp. The general store closes by Labor Day and reservations are required through Recreation.gov in summer. No RVs over 35 feet.

The middle Glacier option — 87 sites in a deep cedar-hemlock grove at the head of Lake McDonald, with the Trail of the Cedars boardwalk and the Avalanche Lake trail starting steps from the campground entrance. Cell service is nonexistent, the canopy keeps things cool even in August, and the location splits the difference between Apgar and the high country at Logan Pass. Reservations through Recreation.gov; the campground typically opens in late June once snow clears the access road.

Yellowstone's only year-round campground sits at 6,200 feet just inside the North Entrance from Gardiner, Montana. Mammoth's 85 sites are open to elk that wander through camp constantly — calving season in June can close loops on short notice. The Mammoth Hot Springs terraces are a 10-minute walk, and the Lamar Valley is a 45-minute drive east on a road that stays open in winter. Reservations are required May through October; sites are first-come, first-served the rest of the year. Bring a sleeping bag rated for 20°F any month.

The classic gateway to the Bob Marshall Wilderness. Holland Lake's 39 sites sit on the north shore of a half-mile-long alpine lake at 4,000 feet in the Swan Range, with the Holland Falls trail (1.5 miles to the falls) and the Holland-Gordon Pass trail into the Bob both starting from the campground. The Holland Lake Lodge across the bay serves dinner and rents canoes. Reservations through Recreation.gov in summer; the campground stays open through September. No hookups.

The deepest natural lake in Montana — 492 feet — sits in the Flathead National Forest northwest of Whitefish, and the campground's 39 sites hug the shore in a Douglas fir forest. Tally is a Forest Service classic: swim beach, canoe launch, no hookups, and no cell service. The drive in is 15 miles of well-maintained gravel from US-93. Reservable through Recreation.gov for summer dates; a small block stays first-come, first-served. The shoreline trail loop is one of the best easy hikes in the Whitefish range.

Greenough Lake's 18 sites sit at 7,400 feet along Rock Creek in the Custer Gallatin National Forest, just below the Beartooth Highway switchbacks above Red Lodge. The campground is a launching point for the all-day climb to 12,799-foot Granite Peak — Montana's highest summit — and a quieter alternative to the busier Cooke City-side campgrounds for Beartooth travelers. Stocked trout in the lake, classic Forest Service ambiance, no hookups. Reservable through Recreation.gov from late June through September.

Pine Creek sits in the Custer Gallatin National Forest above the Yellowstone River in Paradise Valley, the dramatic 50-mile corridor between Livingston and Yellowstone's north entrance. The 25 sites are nestled in a Douglas fir forest at 5,600 feet at the foot of the Absaroka Range, with the Pine Creek Falls and Pine Creek Lake trails climbing directly from camp. It's a strong Yellowstone overflow option when Mammoth and the in-park campgrounds are full, and the access to the Absaroka backcountry is the real draw. Reservable, no hookups.