Gideons International, 6 Mount Vernon St, Nashua, NH 03064, US

The Unitarian Universalist Association is the national headquarters of the faith. The building was originally headquarters of the Unitarian faith until Unitarianism and Universalism merged in 1961. The lobby of the building is open to the public and features a book store stocking materials about the faith and also about the history of Beacon Hill. There's an original John Singleton Copley painting above the mantle in the store, so it's worth a peek if you are an art fan. The administrative offices are upstairs. The Association hosts large-scale meetings at headquarters as well. Tours of the building may be arranged ahead of time.