Garrison is a census-designated place (CDP) in Powell County, Montana, United States.

[5] who was also the father-in-law of Henry Villard, the man who finally pushed the Northern Pacific Railroad to completion in 1883.

[6] Garrison is just east of Gold Creek, where the 'golden spike' was driven on September 8, 1883 to mark the completion of the line.

Garrison was also a division point for the Northern Pacific; as well as its successors Burlington Northern, Montana Rail Link, and BNSF, with traffic heading east to Helena or south and east to Butte.

According to the United States Census Bureau, the CDP has a total area of 9.5 square miles (25 km2), all land.