Tomorrow, on the Saturday of OHNY Weekend (Oct. 17), urban wonks will have an extraordinary opportunity to visit two of the most important buildings in New York City government: City Hall and the Manhattan Municipal Building. Open Access to City Hall has been organized by the Public Design Commission, the official design review agency that advocates for excellence and innovation in the city’s public realm. PDC officials will be on-site throughout speaking about the building’s stunning landmark interiors. And before or after you visit the seat of city government, don’t miss the Manhattan Borough President’s Map Display, just across Centre Street, for a truly historic display of the 1820 Randel Farm Maps, the first to plot the grid established by the Commissioners’ Plan of 1811.


M-City Hall, interior rotunda_credit Andrew Moore

City Hall

12:00 pm4:00 pm.

Completed in 1812, New York’s City Hall is one of the oldest City Halls in the nation still serving its original purpose. It is the third home of New York’s government, but the first to be built specifically as a municipal seat. It is a National Historic Landmark and an NYC Landmark, and the rotunda, lit by a central oculus and graced by a “floating” staircase, is an NYC interior landmark. The plaza, rotunda, City Council chamber, and Governor’s Room will be open during OHNY Weekend, and visitors will be able to chat with staff from the Public Design Commission and Richard Southwick, Director of Preservation with Beyer Blinder Belle. Long lines are expected, so arrive early!


M-Manhattan Borough Presidents Map Display

Manhattan Borough President’s Map Display

10:00 am4:00 pm.

NYC Borough Presidents are responsible for maintaining the official maps for their borough. On OHNY Weekend, the Manhattan BP Gale Brewer’s office will display an historically essential map in the development of Manhattan—executed by John Randel in 1820—that has never been displayed in full. This map is the first that plotted the 1811 “Commissioner’s Plan” which established the Manhattan street grid—from Houston St. to 155th Street—and also encompasses the rest of the island, from The Battery to Inwood. The MBP’s Topographical Bureau is the sole repository for these 92 individually hand-drawn and hand-colored panels— which will be assembled into a room-size display, roughly 16 feet by 60 feet.

For true map geeks, there’s a special incentive to arrive at the 10:00 am Saturday opening of the display: Hilary Ballon, curator of The Greatest Grid: The Master Plan of Manhattan at Museum of the City of New York (and Professor of Urban Studies at NYU) will be available to answer visitors’ questions, but only from 10:00 am11:00 am.