For one weekend each year, Open House New York (OHNY) grants access to sites that even most New Yorkers hardly ever see. A highlight of the year’s program is Eero Saarinen’s iconic TWA Terminal at John F Kennedy International Airport, which was closed in 2001 after American Airlines bought TWA and is now rarely accessible to the public.

The 2011 OHNY— a celebration of architecture and design throughout the five boroughs on 15 and 16 October -- is the city’s ninth and is expected to draw a record 200,000 participants. All of the weekend’s more than 300 activities are meant to unlock New York and provide rare access to sites, tours, talks and special performances that exemplify the city’s diverse and culturally rich, man-made environment.

Completed in 1962, the curvilinear TWA Terminal was an icon of modern design and the golden age of jet travel. But the terminal was considered obsolete with the advent of jumbo jet aircraft, and later decommissioned and closed to the public. Now a New York City landmark and in the National Register of Historic Places, it is being renovated for adaptive reuse, some say as a boutique hotel. On 16 October, the project manager from Beyer Blinder Belle Architects and Planners, which is overseeing the renovation of the TWA Terminal, and the Port Authority of New York and New Jersey’s manager of JFK’s physical plant and redevelopment, will speak about the terminal’s renovation and redevelopment. OHNY participants also will be able to walk through select parts of it.

On 15 October, Chris Pellettieri, a stone carver at the Cathedral Church of St John the Divine in Manhattan’s Morningside Heights, will give a workshop demonstrating the ancient and traditional techniques of stone carving. Construction on the Gothic church began in 1892 and is still incomplete.

A little farther downtown, visitors will have the chance to learn more about Lincoln Center for the Perfoming Arts, a 16-acre campus that dates back to the 1960s and is home to the Metropolitan Opera House, Avery Fisher Hall, Alice Tully Hall and other legendary cultural facilities. On 15 October, members of the design team responsible for Lincoln Center’s recent redevelopment will give tours of their work.

In Brooklyn, Caliper Studio will give tours of Nitehawk Cinema, a movie house in Williamsburg that opened last year. This tour includes the three-screen cinema/café and bar, built in a two-story, mid-century warehouse with a yellow brick facade, plus one of three residential floors above the warehouse. The residential floors’ custom, zinc panel façade contains 2,000 hand-cast glass disks, backlit by low-voltage LED lights; décor in the café includes old barbershop cabinets in place of traditional liquor shelves, while 1950s car bucket seats provide seating in the theatres.

Many OHNY activities require advance reservations, with a $5 processing fee for most reservations made on its website. A VIP Passport, which provides a participant and his or her guest front-of-the-line access to all sites and programs that do not require advance reservations, is available for a tax-deductible donation of $150.  

OHNY is one of 11 city programs in the Open House Worldwide network; the first Open House weekend took place in London in 1992.

“We saw Open House London as a way of helping the wider community to become more knowledgeable, engage in dialogue and make informed judgments about architecture,” said founder Victoria Thornton, a writer and researcher who felt frustrated by the barriers between architecture and the general public. 

Programs take place in the spring in Tel Aviv; in the summer in Melbourne; and in the autumn in London, Dublin, Slovenia, New York, Barcelona, Galway, Jerusalem, and, new this year, Chicago and Helsinki. There will be an Open House program in Rome for the first time in 2012.