Our Pick
Posted on @rawstates
The Tabernacle's roof
1867
Temple Square, Salt Lake City
Leon7 · CC BY-SA 3.0 · Wikimedia Commons
A 150-foot lattice dome built without a single interior column, using wooden pegs and rawhide because nails were scarce. The acoustics are exact enough that a pin dropped at the pulpit is audible at the back, which guides still demonstrate.
That was 1 of the hidden places.
Location: documented spot
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