The town of Calhan is a Statutory Town in El Paso County, Colorado, United States. Calhan straddles U.S. Route 24. The population was 896 at the 2000 census. In 2008, the population was estimated to have declined slightly to 869. According to the United States Census Bureau, the town has a total area of 1 square mile (2.6km2), all of it land.