Locust Gap, PennsylvaniaLocust Gap is an unincorporated community in Northumberland County, Pennsylvania, United States. It is located approximately two miles southwest of Mount Carmel.GeographyLocust Gap is located at an elevation of 1191 feet.Major roadsPennsylvania Route 54Pennsylvania Route 901DemographicsThe United States Census Bureau defined Locust Gap as a census designated place in 2023.