Dauphin County ITReference dataset showing the political boundaries of the municipal subdivisions in Dauphin County. Most likely derived from a PennDOT dataset in the early 1990s. *Note: On February 19th, 2026 the legal boundary for Hummelstown and Derry Township was modified in Dauphin County's GIS data to reflect Ordinance NO. 94-3. Ordinance was issued by the Borough of Hummelstown to annex the tract of land belonging to the Lower Dauphin School District from Derry Township to Hummelstown. This annexation affected parcels 31-042-001, 31-042-033, 31-042-032 , 31-042-028, and 31-057-001. Copies of the ordinances can be requested from the affected municipalities.ArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/695cea4e15ad4452bee59fcca75ad5ae_0engDauphin County GIS Data PortalPublicMunicipal Boundaries [Pennsylvania--Dauphin County]Web servicesPennsylvania--Dauphin CountyPennsylvaniaLast Modified: 2026-02-20