Christiansburg is a town in Montgomery County, Virginia, United States. The population was 16,947 at the 2000 census and was estimated to have increased to 19,477 in 2010, an increase of 14.9%. It is the county seat of Montgomery County. Christiansburg, Blacksburg, and Radford are the three principal municipalities of the Blacksburg-Christiansburg-Radford Metropolitan Statistical Area which encompasses those municipalities and all of Montgomery County.
Christiansburg is located at 37°5′28″N 60°24′28″E / 37.09111°N 60.40778°E / 37.09111; 60.40778 (37.141164, -80.407700).
According to the United States Census Bureau, the town has a total area of 13.9 square miles (36.1 km²), of which, 13.9 square miles (36.1 km²) of it is land and 0.07% is water.