Montana Highway 16 is a 152.371-mile-long (245.217 km) state highway in the U.S. state of Montana. It begins in West Glendive at a Business Loop of Interstate 94 (I-94), and ends at the Port of Raymond on the Saskatchewan border. The northern portion from U.S. Route 2 at Culbertson to the Canada–United States border is proposed as part of the Theodore Roosevelt Expressway.

Glendive is a city in and the county seat of Dawson County, Montana, United States, and home to Dawson Community College. Glendive was established by the Northern Pacific Railway when they built the transcontinental railroad across the northern tier of the western United States from Minnesota to the Pacific Coast. The town was the headquarters for the Yellowstone Division that encompassed 875 route miles (1,408 km); 546 (879) in main line and 328 (528) in branches with the main routes from Mandan, North Dakota, to Billings, Montana, and from Billings to Livingston. The town of Glendive is an agricultural and ranching hub of eastern Montana sited between the Yellowstone River and the Badlands. Makoshika State Park is located just east of Glendive.