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If the auditorium happens to be open, take the opportunity; it is not guaranteed, so I would not build the whole 45 minutes around waiting for it.
Unexpected schedule squeeze. I will have maybe 45 minutes, and I care much more about the architecture than “seeing every room”. Grand Staircase, Grand Foyer, Library-Museum, salons - what deserves the time first?
If the auditorium happens to be open, take the opportunity; it is not guaranteed, so I would not build the whole 45 minutes around waiting for it.
For architecture, I would protect the Grand Staircase and Grand Foyer first. They are the two spaces where the building’s scale and decorative programme make the strongest impression.
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