Marysville is a small unincorporated community in Lewis and Clark County, Montana, United States. In the 1880s and 90's it was a bustling mining town of three thousand residents, and was the center of gold mining in Montana. The town was named by Thomas Cruse, mine owner, to honor Mary Ralston the wife of a miner. A few buildings remain, including a baseball field with bleachers. The population now consists of a few local residents, most of whom commute to and work in nearby Helena.
Just up the dirt road is Great Divide Ski Area, while down the road is the defunct Silver City Saloon on Highway 279.
In 2010 there were news reports that recent exploration of the richest gold mine in the area, the Drum Lummon Mine, has led to possible new discoveries. The lower levels of the Drum Lummon were allowed to flood when the mine was closed in 1904 during litigation. Sentiment in the town is mixed regarding possible resumption of extensive mining operations.