Our Pick
Posted on @rawstates
Lock 27, where the whole Mississippi goes around a ledge of rock
1953
Chouteau Island, Granite City, Illinois
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A few miles above St. Louis the riverbed rises into an outcrop of bedrock that low water turns into a wall, the chain of rocks the place is named for. The Corps of Engineers answered it with an 8.4 mile canal cut on the Illinois side and two lock chambers, the main one 1,200 feet long, which opened to traffic in February 1953. More cargo now moves through here than through any other single navigation structure on the Mississippi system.
That was 1 of the hidden places.
Location: documented spot
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