tag:digital.library.illinois.edu,2005:/items/a3224f80-994e-0134-2096-0050569601ca-0
Illinois, Mackinaw quadrangle
2022-09-15T18:31:53Z
tag:digital.library.illinois.edu,2005:Item/70032
2016-11-30T19:19:58Z
2022-09-15T18:31:53Z
Illinois, Mackinaw quadrangle
Contour interval 10 feet.
University of Illinois at Urbana-Champaign Library