Blackfeet Indian Reservation in the context of Birch Creek (Pondera County, Montana)

The Saint Mary River (Blackfoot: Apahktóksipisskan), is a cross-border tributary of the Oldman River, itself a tributary of the South Saskatchewan River. The Saint Mary together with the Belly River and Waterton River drains a small portion of Montana, in the United States, to the Hudson Bay watershed in Canada.

The river rises as a stream on Gunsight Mountain in Glacier National Park and flows into Gunsight Lake, then flows into Saint Mary Lake, exits the park and flows on into Lower St. Mary Lake in the Blackfeet Indian Reservation. From the reservation, the St. Mary River flows into Alberta and into the St. Mary Reservoir. It flows into the Oldman River which eventually reaches the Saskatchewan River.

The Cut Bank Creek is a tributary of the Marias River in the Missouri River basin watershed, approximately 75 mi (123 km) long, in northwestern Montana in the United States, which having deeply eroded steep cliff banks eponymously gives name to the cut bank formal terrain term of geological science.

It rises in the Rocky Mountains in Glacier National Park at the continental divide and flows ENE onto the foothills and plains of the Blackfeet Indian Reservation, then southeast, past Cut Bank, Montana where it forms a scenic gorge 150 feet (46 m) deep spanned by an elevated railway bridge just a mile from the town's Amtrak rail transport system passenger station and BNSF railway freight yards. The river and cliff there are prototypical giving rise to the eponymous formally named "cut bank" geographic terrain feature archetype.

Glacier County is located in the U.S. state of Montana. As of the 2020 census, the population was 13,778. The county is located in northwestern Montana between the Great Plains and the Rocky Mountains, known to the Blackfeet as the "Backbone of the World". The county is geographically and culturally diverse and includes the Blackfeet Indian Reservation, Glacier National Park, and Lewis and Clark National Forest. The county is bordered by 75 miles of international boundary with two ports of entry (Piegan and Del Bonita) open year-round and one seasonal (Chief Mountain) international border crossing into Alberta, Canada.