Cowles Bog is a four-thousand-year-old wetland complex in Indiana Dunes National Park near Chesterton, Indiana, made up of fen, marsh, wet meadow, swamp, pond, and bog-like habitats between dune ridges and low wetlands draining toward Lake Michigan. Closely tied to ecologist Henry Chandler Cowles, the area helped establish the concept of ecological succession and drew international scientific attention, especially after the 1913 International Phytogeographical Excursion. Its scientific importance later supported preservation of the wider Indiana Dunes, including efforts by Dorothy Buell and the Save the Dunes Council. Recognized for both ecology and history, it became a National Natural Landmark in 1965 and joined the National Register of Historic Places in 2025.

Porter, Indiana · USA