Fort Indiantown Gap, also referred to as "The Gap" or "FTIG", is a census-designated place and U.S. Army post primarily located in Lebanon County, Pennsylvania. A portion of the installation is located in eastern Dauphin County. It is located adjacent to Interstate 81, 23 miles (37 km) northeast of Harrisburg, just north of the northern terminus of Pennsylvania Route 934 at I-81's Exit 85. The installation is an active National Guard Training Center and serves as headquarters for the Pennsylvania Department of Military and Veterans Affairs and the Pennsylvania National Guard. The fort surrounds Memorial Lake State Park. It is served by the Annville, Pennsylvania post office. As of the 2010 census the population was 143 residents.