These data are a qualitatively derived interpretive polygon shapefile defining surficial sediment type and distribution, and geomorphology, for nearly 1,400 square kilometers of sea floor on the inner-continental shelf from Fenwick Island, Maryland to Fisherman’s Island, Virginia, USA. These data are classified according to Barnhardt and others (1998) bottom-type classification system, which was modified to highlight changes in secondary sediment-types such as mud and gravel across this primarily sandy shelf. Most of the geophysical and sample data used to create this interpretive layer were collected as part of the Linking Coastal Processes and Vulnerability: Assateague Island Regional Study project (GS2-2C), supported by the U.S. Department of the Interior Hurricane Sandy Recovery program. Additional sample data were provided by the Maryland Geological Survey and the Virginia Division of Geology and Mineral Resources. Additional hydrographic data were available through the National Oceanographic and Atmospheric Administration’s National Ocean Service surveys collected between 2006 and 2014. The primary objective of the Hurricane Sandy Recovery program is to provide science for coastal resilience, and these interpretive data support the program goal by supplying regional geologic framework information for the management of coastal and marine resources. Accurate data and maps of seafloor geology are important first steps toward protecting fish habitat, delineating marine resources on the inner-shelf, understanding sediment transport pathways, and assessing environmental changes because of natural or human effects. The Assateague Island Regional Study project is focused on the inner-continental shelf of Maryland and Virginia, north of Chesapeake Bay entrance. Data collected during the mapping portion of this study have been released in a series of USGS data releases (https://woodshole.er.usgs.gov/project-pages/delmarva/). A combination of geophysical and sample data including high resolution bathymetry, acoustic-backscatter intensity, bottom photographs, and sediment samples are used to create this seafloor interpretation.