[8] Several months after Delphi was founded, it was designated as the county seat.

[9] The Barnett-Seawright-Wilson House, Carroll County Courthouse, Delphi City Hall, Delphi Courthouse Square Historic District, Delphi Methodist Episcopal Church, Foreman-Case House, and Niewerth Building are listed on the National Register of Historic Places.

[10][11] Local heritage centers on the Wabash and Erie Canal, a canal and towpath that once bound together northern, central, and southern Indiana.

According to the 2010 census, Delphi has a total area of 2.73 square miles (7.07 km2), all land.

[12] At the 2010 census there were 2,893 people, 1,135 households, and 694 families living in the city.

There were 1,270 housing units at an average density of 465.2 per square mile (179.6/km2).

At the 2000 census there were 3,015 people, 1,161 households, and 748 families living in the city.

There were 1,241 housing units at an average density of 485.4 per square mile (187.4/km2).