Open House New York (OHNY) is back for another year, opening usually closed doors to the public. They've now announced this year's offerings, and you can sign up now to reserve spots (though some tours do not require reservations); the event takes place October 9th and 10th. The weekend is free of charge, but they're offering up a $150 Passport, which will allow you and a guest front-of-the-line access at all sites and programs that do not require advance reservations.
Some of the spots you can check out include the Fort Tryon Park Heather Garden & Fort Tryon Cottage (Queens), the Conference House (Staten Island), Bartow-Pell Mansion (the Bronx), the Gatehouse (Manhattan), and for the daring, the Gowanus Canal Sponge Park (Brooklyn).
If you check out some spots, send us your photos or tag them "Gothamist" on Flickr!