Mount Brown is a 6,958-foot-elevation (2,121-meter) mountain summit located in Liberty County, Montana, United States.

[4] Mount Brown is an exposed laccolith composed of syenitic and monzonitic trachytes created by an igneous intrusion through older Jurassic and Cretaceous sedimentary rocks during the Eocene, about 50 million years ago.

Over time, erosion of the sedimentary rock has exposed the solidified laccolith which is more resistant to weathering.

The Sweet Grass Hills, which are centered in buffalo hunting territory, are sacred to the Blackfoot and other tribes.

The wettest period of the year is generally May through August, with up to 20 inches of precipitation falling annually on the peak.