To support its interactivity, the 1811 plan has been georectified. The avenues run parallel to the island, tilting to the northeast, rather than true north. The deviation from true north is close to 29 degrees. The georectification enables users to relate the 1811 plan to the city today by using the slide to transition between past and present, or by typing a modern address in the address finder.
Hot spots explain several key features of the map and are searchable by the index.
There are three original manuscript copies of the 1811 Plan. The version presented in this interactive is from the Manuscripts and Archives Division, The New York Public Library, Astor, Lenox and Tilden Foundations (MssCol 605). The map is drawn in ink on paper, wax seals are attached at the bottom, and it measures 106 x 30 7/16 inches.