Our Pick
Posted on @rawstates
The Elgin watch observatory
1910
312 Watch Street, Elgin, Illinois
Public domain · Wikimedia Commons
The National Watch Company came to Elgin in 1864 and grew into the largest watch factory in the world, turning out tens of millions of movements before the plant closed in 1965 and was pulled down the year after. What survives is the small observatory it put up in 1910 to find out what time it actually was. Staff tracked stars to fix sidereal time, checked it against the sun, and set the factory's watches to a fraction of a second.
That was 1 of the hidden places.
Location: historic site
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