The Rum River is a slow, meandering stream that connects Minnesota's Mille Lacs Lake with the Mississippi River. It runs for 151 miles (243 km) through the communities of Onamia, Milaca, Princeton, Cambridge, Isanti, and St. Francis before ending at the city of Anoka, roughly 20 miles northwest of Minneapolis. It is one of the six protected Wild and Scenic rivers in Minnesota.

Mille Lacs County is a county in the East Central part of the U.S. state of Minnesota. As of the 2020 census, the population was 26,459. Its county seat is Milaca. The county was founded in 1857, and its boundary was expanded in 1860.