Made in Manhattan

Photo: Chess, Turtle Bay, East Side, NYC © Flickr user mccuba48 under Creative Commons.

What's this? And how do they move the pieces?

Waymarking.com ('tools to share and discover unique and interesting locations on the planet') explains in Giant Chessboard on Wall of Building - New York, NY: 'A giant chessboard is on the blank wall of an apartment building located on 212 E. 48th Street east of 3rd Avenue on the east side of Manhattan.'.

As for the next question, how they move the pieces:-

An upscale apartment building at 212 E. 48th Street in the Turtle Bay area of Manhattan happens to have a completely blank wall on its west side and a small open lot used as a pocket park below which makes the wall very visible, a rare combination in midtown Manhattan.

The owners of the building next door at 747 3rd Avenue, the Kaufman brothers, were unhappy with the appearance of the blank wall and decided to make this arrangement useful and unique by installing a four storey high giant chessboard and recreating great chess games of the past. The chessboard is claimed to be the largest in the world.

The board is constructed of large metal beams. 2.5' diameter blue and tan round disks, with the standard chess symbol inscribed, are used. Moves are made every Wednesday by workers using hydraulic cherry pickers. A flag next to the board signals who has the next move or the status of a finished game.

Is the chessboard really the largest in the world?