This U.S. Geological Survey (USGS) Data Release provides a digital geospatial database for the Bedrock geology of the Evitts Creek and Patterson Creek quadrangles, Maryland, Pennsylvania, and West Virginia from the original map of de Witt and Colton, 1964. Attribute tables and geospatial features (points, lines, and polygons) conform to the Geologic Map Schema (GeMS, 2020) and represent the geologic map as published in the U.S. Geological Survey Bulletin 1173 with no adjustments made to any of the map data. The Description of Map Units (DMU) summarizes descriptions of the same lithostratigraphic units from adjacent maps published by the same author in the area and is expanded from the text published in the the original report. Some revisions to stratigraphic nomenclature were made to conform with modern usage. When symbolized according to the accompanying Federal Geographic Data Committee (FGDC) style file, this data release presents the geologic map as shown on the published map by de Witt. MapUnitPolys labels may be symbolized according to the accompanying FGDC Opentype Font file (FGDCGeoAge) for special geologic age characters. Surficial map data is not represented in this geodatabase. Surficial map data is not represented in this geodatabase.