Forest roads start close to town
Missoula sits at 3,169 feet where the Clark Fork, Bitterroot and Blackfoot rivers meet, in a hub of five valleys ringed by the Bitterroot Range, the Sapphires, the Garnets, the Rattlesnake Mountains and the Reservation Divide. The useful consequence for a campervan is that national forest land begins close to the city. The Lolo National Forest wraps around Missoula, the Bitterroot National Forest picks up to the south, and on both you can camp outside a developed campground without booking anything.
Know the rules before you count on that. A Northern Region forest order caps how long you can sit still: on Montana national forests, 16 consecutive days at a single site and 32 cumulative days in a calendar year. Cross Lolo Pass into Idaho and the same order tightens to 14 consecutive and 28 cumulative days. Where you can take the van is set by each forest's Motor Vehicle Use Map, which is free to download and worth having offline, because routes not shown on it are not open to public motor vehicle travel no matter how established the track looks. Dispersed sites have no water, no toilets and no bins, so pack everything out, use an existing fire ring, and bury waste at least 200 feet from any water source. Finding a legal spot in the first place is what boondocking apps are for.
If you would rather have a reservation, the Lolo National Forest runs around 20 campgrounds and the Bitterroot about 23, many of them bookable through recreation.gov. Montana's state parks near town (Milltown, Fish Creek and Council Grove) use ReserveAmerica, open bookings three months ahead, and release unreserved sites as first-come on the day of arrival.
Bear storage is one job the van already does
The Lolo National Forest falls under the Northern Continental Divide Ecosystem food and attractant storage order, in force each year from March through December, and the Bitterroot runs its own. The order accepts attractants secured inside a hard-sided vehicle, RV, trunk, cab or trailer cab, so a campervan is itself compliant storage. The alternatives are a certified bear-resistant container, approved electric fencing, or hanging everything 10 feet up and 4 feet out from a support. Attractants include pet food, drinks, hygiene products and empty containers, not just food.
US-12 over Lolo Pass, and the reason you fuel up first
Lolo Pass is about 40 miles south-west of town at 5,233 feet, with a visitor centre at the top. Beyond it, US-12 follows the Lochsa River, Wild and Scenic since 1968, for roughly 70 miles to Lowell, losing nearly 2,000 feet on the way. This is a long stretch of highway with very little on it. Limited services begin at Powell, 13 miles past the pass, and it is 65 miles from there to Lowell, with campgrounds and ranger stations standing in for towns. Lewiston is 170 miles from the summit.
Hot springs are the other reason to point the van this way. Lolo Hot Springs sits on US-12 on the Montana side, inside the Lolo National Forest between town and the pass, with RV, tent and cabin sites of its own. Quinn's Hot Springs is north-west of Missoula on Highway 135 at Paradise, and sells day-use swim sessions to people who are not staying overnight, booked in advance.
The Bitterroot, and the roads still shut in May
South of Missoula, US-93 runs about 95 miles down the Bitterroot Valley to Lost Trail Pass at the Idaho line, through Lolo, Stevensville, Victor, Corvallis, Hamilton, Darby and Sula. The Bitterroot Range on the west side has steep faces and deep canyons such as Blodgett; the Sapphires on the east are rounder, drier and much less forested. Skalkaho Pass, Montana Highway 38, crosses the Sapphires from Hamilton toward Philipsburg on a road that is largely gravel. Montana DOT lists its middle section, mileposts 14 to 38, among the roads it closes for the winter without publishing fixed dates, so check 511 for the current status and check your rental agreement about unpaved roads before you plan around it.
That late opening is the pattern for high ground across the region. Glacier National Park is roughly 150 miles north. Going-to-the-Sun Road there does not usually open end to end until late June at the earliest, and it bars vehicles over 21 feet on its central section, which is worth checking against the van you book. Yellowstone National Park is far enough to be a trip in itself rather than a day out, and most of its roads are open only from about mid-April to the end of October.
Summer here suits a van without hookups. On the 1991-2020 normals, July and August average about 34 degrees Fahrenheit between the daily high and the overnight low, and September about 30, so even a hot afternoon usually turns into a sleepable night. June is milder in both directions, closer to 27. Fire danger is the thing to watch instead: the Lolo National Forest posts a current fire danger rating and campfire restrictions that can change mid-trip.
Picking up and heading out
Missoula Montana Airport is about four miles north-west of the city, which makes collection unusually quick. It runs year-round nonstop service to Denver, Seattle and Salt Lake City, and Uber, Lyft, local shuttles and the Mountain Line bus all serve the terminal, so meeting a host away from the airport is no great inconvenience. For a first night out, Rock Creek joins the Clark Fork near Clinton just east of town and is a well-known fly-fishing stream, holding rainbow, brown and westslope cutthroat trout along with threatened bull trout.