Big Arm Area - Flathead Lake State Park
RV Guide


Big Arm Area at Flathead Lake State Park is located on the western edge of Flathead Lake, the largest natural freshwater lake, by surface area, west of the Missouri River. It is located approximately 80 miles north of the city of Missoula, MT, but less than five miles from the tiny towns of Elmo and Big Arm. The 41 campsites that are suitable for RVs are typically fairly roomy and surrounded by mature ponderosa pines, cottonwood trees, and juniper bushes, giving them plenty of privacy. The campsites are level and well-maintained, most of them right along the water’s edge.

This is a great area for viewing wildlife, from squirrels to black bears, and the clear, deep lake is well-known for its trophy-sized bull and rainbow trout, particularly in the fall season. If you enjoy swimming, make sure to pack your swimsuit and beach shoes in the campervan as well. The long pebble beach in this area has been designated as a swimming area and is popular with both RV visitors and locals. The waters outside of the swimming area are appreciated by boating enthusiasts of all kinds, including those with kayaks, motorboats, and sailboats.

RV Rentals in Big Arm Area - Flathead Lake State Park



The Big Arm Campground in Flathead State Park is just under two miles northwest from the tiny town of Big Arm, Montana, and less than four miles southeast of the equally tiny town of Elmo, Montana. Highway 93, which leads to the Big Arm Area of Flathead Lake State Park from both the north and the south, is a beautiful, scenic road that hugs the beaches of the 197-square-mile Flathead Lake. There are some twists and turns as well as some gradual elevation changes along the road, but for the most part, they should be simple enough to traverse in a big rig or with a trailer. Highway 28 travels to the lake through rolling hills as it approaches the park from the east, bypassing the majority of the twists and turns, but is somewhat less scenic until you are closer to the campgrounds. Inside the park, the roads are paved with gravel roads and are slightly narrower. The campsites have well-maintained, level areas to back your rig into, and there are roomy parking areas near the marina and the dock, as well as additional parking by the yurts.


Public Transportation

Campgrounds and parking in Big Arm Area - Flathead Lake State Park

Campsites in Big Arm Area - Flathead Lake State Park

Reservations camping

Big Arm Campground

Forty-one campsites are open for RVs and available for reservation. Reservations can be made from two days up to nine months in advance. The spots range quite a bit in size, varying from smaller sites, suitable only for smaller RVs or trailers up to 18 feet long to larger sites which will accommodate a 35-foot vehicle or trailer. All motorized vehicles and trailers must fit entirely within the campsite; any equipment that does not must be parked outside the campgrounds or a second campsite will need to be purchased.

Each site provides room for up to eight people and is equipped with a fire ring and grill, picnic tables, and bear-proof food storage lockers. The majority of the sites are right near the edge of the water, the exceptions being sites A1-A3 and B17-B22. In the summer months, between mid-May and mid-September, a water house with showers is available for campers to use. Generators are allowed during the daytime but prohibited during quiet hours, from 10 PM to 7 AM. Pets are welcome at the Big Arm Campground but must be contained or be restrained by a six foot or shorter leash at all times. While they are welcome on the trails in the area, they are not allowed in waters designated for swimming or on the beaches nearby.

Seasonal activities in Big Arm Area - Flathead Lake State Park



The Big Arm Campground is situated on the shores of Flathead Lake, a very popular body of water for pleasure boating. The size and the stunning beauty of the lake attracts enthusiasts with all sorts of watercraft, from windsurfing boards and kayaks to pontoons and sailboats. Both motorized and non-motorized boats are permitted on the lake as long as they are under 50 feet long. Towed recreation like water skiing is allowed on the lake from sunrise to sunset, provided a distance of at least 50 feet is maintained from any swimmers or designated swimming areas.


Pack your swim gear in your trailer and head to the southwest portion of the lake. This is designated as a no wake zone so that swimmers can safely enjoy the lake. The clear waters of Flathead Lake draw swimming competitions here on a regular basis, and the long pebble beach is a popular area for both swimmers and sunbathers. While your canine companion is welcome in most areas of the Big Arm Campground, they are not permitted in designated swimming areas or on the beaches nearby.

Visiting Wild Horse Island

Big Arm campground is one of the more popular places to launch a boat for Wild Horse Island, an island in the southern portion of Flathead Lake. The island, which is only accessible by boat, has a plethora of wildlife, including yellow-pine chipmunks, bighorn sheep, a population of bald eagles, and, of course, wild horses. The bighorn sheep are so abundant on this small parcel of land that some are transported to other areas to help bolster sheep populations there as well.



Get your fishing gear out of the rig since there are several species of fish that reside in Flathead Lake including pike, bass, kokanee, salmon, yellow perch, and whitefish. The most sought after species in the deep, cold water of the lake are the bull and rainbow trout, which reach very large sizes in this deep lake, often larger than twenty pounds. Trolling gear will need to be packed in the campervan or rented at the marina if you are angling for lake trout during the majority of the year, as they inhabit the deeper parts of the lake. In the fall, around September and October, the trout are more likely to come nearer the shoreline. To fish this area of Flathead Lake you will need both a Montana fishing license and a tribal fishing license.


Juniper Jaunt and the Bluebird Boulevard trails together cover around 2.5 miles of ground and have trail heads near the campground. They are fairly undemanding hikes that wind through the large ponderosa pines and juniper trees that dominate the landscape. Remember to bring your camera and binoculars in your camping trailer. There are gorgeous landscape views as well as many opportunities to spot wildlife along the trails, including several species of birds, mule deer, white-tailed deer, squirrels, and the occasional black bear.


The Big Arm Area of Flathead Lake Park is an excellent spot to spot all sorts of birds so be sure to pack your birding kit in your campervan. There are several species of waterfowl that spend the majority of their time on the lake, including loons, ducks, geese, and swans. Shorebirds, such as American avocets and sandhill cranes, can often be spotted as they search for food near the beaches. Osprey are also known to nest near Flathead Lake, and Bald Eagles who nest on the lake’s islands can frequently be seen wheeling in the sky as they hunt.