The folks at Civil War Washington have put together a wonderful GIS tool for exploring CW-era Washington, D.C. You can see the data overlaid on a contemorary map of the District of Columbia, a modern map or satellite image. All sorts of data is included, such as identification of residences, wartime hospitals, theaters, churches, bawdy houses, forts, police stations, and so on. You can also use a “time slider” to change the date from 1859 to 1866 to see the profusion of small hospitals around the city as the war went on. From the description:

Civil War Washington has created a project geographical information system (GIS), which combines historical maps and historical information with modern technology. The dynamic map interface allows users to examine digitized period maps of the District, to move between current and historical views, and to select one or more feature layers (such as hospitals, theaters, and freedmen’s villages) and view information about these locations.

The standard historical basemap used by Civil War Washington is Albert Boschke’s Topographical Map of the District of Columbia. According to the Library of Congress, Boschke was a German-born civil engineer who had completed a detailed map of Washington, DC for the year 1857, documenting the location of all buildings in the District. He and his team continued to survey the District leading up to the ultimate publication of this comprehensive topographical map in early 1861. The United States War Department seized the map (and the engraved copper plates from which it was published) shortly after publication, near the beginning of the Civil War.

Along with Boschke’s historical map, the Civil War Washington GIS includes 17 point, line, and polygon layers representing locations of bawdy houses, canals, churches, forts, fort boundaries (outlining the geographical extent of the fort), freedmen’s villages, government buildings, hospitals, omnibus routes, police stations, police precincts, railroad lines, streams, street railways, theaters, voting wards, and residences of Walt Whitman. The placement of each point is approximate and has often been based on relative location information (such as intersections). Users should consider the approximate nature of the locations when drawing conclusions or basing interpretations on the Civil War Washington map.

The instructions are here, but you might as well just dive in yourself.

Thanks to CWT user kholland for bringing this site to my attention.

Oh, I almost forgot — Madame Hays’ is in the middle of the block on Twelfth, between E and F, Northwest.

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