First-Ever Doors Open Pittsburgh: October 1 & 2
"Doors Open" events were pioneered in Europe, and are when a community's culture organizations band together to provide a coordinated schedule of events, usually over a weekend, where people get free access to various cultural sites and events, many of which are not normally open to the public.
In North America, Doors Open Toronto is probably the biggest. The Toronto Star even publishes an event guide. (2011 Doors Open Toronto Guide)
But Open House New York Weekend is increasingly a big deal--this year it is October 15 and 16.
Pittsburgh is launching Doors Open Pittsburgh next month.
From the website of the Pittsburgh History and Landmarks Foundation:
... is a FREE, two-day event on the weekend of October 1 & 2 that will provide behind-the-scenes access, or some unique experience, to a collection of iconic buildings in Downtown Pittsburgh. Open buildings will include private clubs, theaters, residences, heritage sites, government offices, hotels, sacred places, and artist and office spaces.
You do not need a ticket or reservation to attend. Simply decide what buildings you want to visit after reviewing the list on www.doorsopenpgh.org and come Downtown to start your adventure! Bring your friends and family and experience downtown in a whole new way.
Doors Open Pittsburgh is partnering with AIA Pittsburgh (a chapter of the American Institute of Architects), Design Center, Green Building Alliance, and PHLF, in cooperation with the Pittsburgh Downtown Community Development Corporation and Pittsburgh Downtown Partnership in this inaugural year.
This former bank vault is now the dining room for the Engineers’ Society of Western Pennsylvania, which is one of the buildings participating in the event.