Geography of Mountrail County, North Dakota

By | April 4, 2024

Mountrail County, located in the northwestern part of North Dakota, is characterized by its vast prairies, rugged badlands, and abundant natural resources. From expansive grasslands and winding rivers to picturesque lakes and unique geological formations, Mountrail County offers a diverse and scenic landscape shaped by its geography, climate, and waterways.

Geographical Overview:

According to Answermba, Mountrail County is situated in the northwestern corner of North Dakota, bordered by Ward County to the east, McLean County to the south, Mercer County to the southwest, and Williams County to the west. It covers an area of approximately 1,942 square miles (5,030 square kilometers) and is home to a population that values its rural character, strong sense of community, and outdoor recreational opportunities.


Mountrail County experiences a continental climate, characterized by cold winters, warm summers, and low precipitation. Winters are long and cold, with average temperatures ranging from below freezing to single digits Fahrenheit (around -18 to -5 degrees Celsius). Summers are relatively short but can be warm, with average high temperatures reaching the 70s to low 80s Fahrenheit (around 21-28 degrees Celsius). Precipitation is minimal throughout the year, with most of it falling during the summer months in the form of rain and occasional thunderstorms.

Prairies and Grasslands:

Mountrail County is predominantly covered by vast expanses of prairie grasslands, which support a variety of plant and animal species adapted to the region’s harsh climate and dry conditions. The county’s prairies are characterized by rolling hills, wide-open spaces, and sweeping vistas, offering panoramic views of the surrounding landscape.

The prairies of Mountrail County are home to a variety of wildlife species, including deer, pronghorn antelope, coyotes, and various bird species. Native grasses such as buffalo grass, blue grama, and western wheatgrass dominate the landscape, providing habitat for grassland birds and other wildlife.

Rivers and Creeks:

Mountrail County is intersected by several rivers and creeks, which play a vital role in shaping the landscape and providing water for irrigation, wildlife habitat, and recreational activities. The Missouri River forms the northern boundary of the county, serving as a major waterway for transportation, fishing, and boating.

Other notable rivers and creeks in Mountrail County include the White Earth River, the Shell Creek, and the Little Muddy Creek, each of which contributes to the county’s natural beauty and recreational opportunities. These waterways are popular destinations for fishing, canoeing, and birdwatching, allowing visitors to explore the scenic landscapes and diverse ecosystems of Mountrail County.

Lakes and Reservoirs:

Mountrail County is home to several lakes and reservoirs that offer opportunities for water-based recreation and relaxation. The largest reservoir in the county is Lake Sakakawea, a man-made reservoir created by the Garrison Dam on the Missouri River. Stretching for over 200 miles (320 kilometers) long and covering an area of approximately 1,340 square miles (3,470 square kilometers) when full, Lake Sakakawea is one of the largest reservoirs in the United States and a popular destination for fishing, boating, and camping.

Other notable lakes in Mountrail County include New Johns Lake, Van Hook Arm, and Shell Lake, each offering its own unique attractions and recreational opportunities. These bodies of water provide scenic backdrops for outdoor activities such as hiking, birdwatching, and wildlife photography, allowing visitors to connect with nature in a tranquil setting.

Badlands and Geological Formations:

In addition to its prairies and waterways, Mountrail County is also home to unique geological formations, including rugged badlands and scenic buttes. The Little Missouri National Grassland, located in the southern part of the county, features spectacular badlands scenery, with eroded cliffs, colorful rock formations, and unique geological features.

The badlands of Mountrail County provide habitat for a variety of plant and animal species adapted to the region’s harsh climate and arid conditions. Visitors to the area can explore hiking trails, scenic overlooks, and interpretive exhibits that highlight the geological and natural history of the region.


Mountrail County, North Dakota, offers a diverse and scenic landscape characterized by its vast prairies, winding rivers, and unique geological formations. Its continental climate provides distinct seasons, each with its own attractions and recreational opportunities. Whether exploring the county’s grasslands, fishing along its rivers and lakes, or hiking through its badlands, Mountrail County invites visitors to experience the natural beauty and outdoor adventures of the Great Plains.