Our Pick
Posted on @rawstates
Effigy Mounds
700
Allamakee County, Iowa
CC0 · Wikimedia Commons
More than two hundred mounds on the bluffs above the Mississippi, many shaped as bears and birds up to 137 feet long, built over several centuries and best read from the air. Twenty descendant nations are consulted on the site's management.
That was 1 of the hidden places.
Location: documented spot
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