Yes just not Christmas eve and Christmas day.
We are closed Christmas eve and Chrismas day, but open the rest of the week. Weekdays from 8 to 4 with tours at the top of the hour, except between 12 and 1. You can go around on your own during the week, but not on the weekend. Weekends tours are at the top of the hour between 9 and 3, except between 12 and 1. You can not go upstairs on your own on the weekends.
I would call them up before making any plans. It's open to the public on weekdays and weekends off season, but not sure about holidays.
Yes, it is public building.
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