Our Pick
Posted on @rawstates
The Bay Model
1957
Sausalito, California
Public domain · Wikimedia Commons
To disprove a scheme to dam the bay and farm it, the Army Corps built the bay itself in a warehouse: two acres of concrete, tidally accurate, a day's cycle running in fourteen minutes. It worked, the plan died, and the model kept being used for real hydrology until computers got better at it. It is still there, still filling and draining.
That was 1 of the hidden places.
Location: historic site
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