1986 Map of Blue Rapids

The hydrology of the region is defined by the Little Blue River and the Black Vermillion River, which wind through a mosaic of townships like Guittard and Murray. For researchers, the map provides a precise look at local infrastructure before further modern consolidation, documenting everything from the Marysville Municipal Airport and rural Landing Strip locations to distinctive geographical markers like Twin Mounds and Indian Mound. Small communities such as St Bridget, Baileyville, and Hollenberg remain clearly delineated, preserving the mid-1980s settlement pattern across Marshall and Nemaha counties.