The Delaware Geospatial Data Sources site provides extensive data and maps, both current and historic, about Delaware's geology and hydrology, as well as information on the state's paleontology, geophysics, earth science, and mineral resources.

Includes GIS for state and local boundaries, Delaware Orthophotography, links to web mapping sites, and information about weather and climate.

The Maryland Geological Survey site provides digital quadrangle geologic maps and digital county geologic maps of Maryland, as well as maps and information about Maryland's general geology, shoreline, gold district, Chesapeake and Ohio Canal Historical Park, surficial sediments of the Chesapeake Bay, shoreline changes of the Tidewater region, county boundries, reservoir bathymetry, and other features. The site also lists the Survey's publications and provides ordering information for those publications.

The Maryland State Geographic Information Committee site provides a list of maps and other publications regarding Maryland produced by Maryland's Department of Housing and Community Development, Department of Natural Resources, Department of Planning, and State Highway Administration. Samples of the maps are provided, as is ordering information. Links to the Maryland Mapping Resource Guide, Maryland's Environmental Resources & Land Information Network (MERLIN) Online, and related sites are also provided.

The New Jersey Bureau of Geographic Information Systems site provides a wealth of maps and other GIS data regarding New Jersey. The site features an interactive map serving New Jersey's Department of Environmental Protection, Department of Geology, and Environmental Management System. The interactive map also covers the Delaware River Basin. The site also features digital orthophoto quarter quadrangle images of the entire state from both 1995 and 2002, CAFRA layers, information about various mapping standards, GPS resources, and related information. In addition, the site provides links to related sites.

The New Jersey Geological Survey: Digital Geodata Series site provides maps and data about New Jersey, including base maps, elevation maps, geologic maps, magnetic anomaly maps, groundwater maps, and surface water maps. The site also provides links to related sites.

The New York State Museum: Geographic Information System Data site provides statewide and regional data about New York. The data includes boundry data, surficial geology data, bedrock geology data, fault data, and data regarding the Upper Saranac Lake watershed. The site also provides topographic maps, a link to the Empire State Oil and Gas Information System, and links to related sites.

Maps of the 18th and 19th century are available for thumbnail viewing, enlargement, printing (though not to full size), and purchase. The descriptive catalog record accompanies each image.

The Pennsylvania Geological Survey provides information about the geology of Pennsylvania, including geology abstracts, geologic hazards, glaciation, fossils, landforms, and oil and gas resources. The Survey also provides digital maps and GIS data regarding Pennsylvania, including geologic maps, topographic maps, aerial photographs, and geospatial data. In addition, the Survey provides information about its publications and links to related sites.