Our Pick
Posted on @rawstates
Lake Renwick, a heron rookery in flooded gravel pits
1990
Plainfield, Illinois
3.0516 · CC BY-SA 4.0 · Wikimedia Commons
These lakes are worked out quarries that supplied aggregate for Chicago's concrete. The pits closed in 1983, groundwater filled everything below the water table, and the county and the state bought the result as open space in 1990. Because the bottom is gravel rather than mud the fishery is unusually rich, and the Illinois Audubon Society calls the rookery here the most valuable in the state. Most of the preserve is shut to visitors from March to mid August so the nesting birds are left alone.
That was 1 of the hidden places.
Location: approximate area
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