 Whereas Capitol Heights itself is an incorporated town in Prince George's County, residents and businesses located in unincorporated towns either nearby, or on the border of Capitol Heights, such as Coral Hills, Walker Mill, Pepper Mill Village, Carmody Hills, Fairmount Heights, and Chapel Oaks, are assigned Capitol Heights addresses, along with the Capitol Heights zipcode of 20743, even though they are not located within the official neighborhood boundaries of Capitol Heights.According to the United States Census Bureau, the town has a total area of , all land.In 1904, Washington, D.C., was growing by leaps and bounds.