Quantico is a town in Prince William County, Virginia, United States. The population was 480 at the 2010 census. Quantico is approximately 35 miles southwest of Washington, D.C., bordered by the Potomac River to the east and the Quantico Creek to the north. The word Quantico is a corruption of the name of a Doeg village recorded by English colonists as Pamacocack.

Marine Corps Base Quantico is a United States Marine Corps installation located near Triangle, Virginia, covering nearly 55,148 acres of southern Prince William County, Virginia, northern Stafford County, and southeastern Fauquier County. Used primarily for training purposes, MCB Quantico is known as the "Crossroads of the Marine Corps".