This is one of five kiosks built with the Queensboro Bridge in 1909 that covered staircases leading to an underground trolly station on 59th street at 2nd Avenue in Manhattan. The trolly system had lines from Manhattan over the Queensboro bridge into different Queens neighborhoods and there was a trolly that actually stopped in the middle of the bridge, allowing passengers to transfer to an elevator building for access to the island.
Trolly service ended in 1957 and the elevator building was demolished in 1970. This kiosk was used as the entrance to the Brooklyn Children's Museum from 1970 through around 1998. It was relocated to the island in 2005 and placed at this location near the tramway in 2006 for use by the Roosevelt Island Historical Society.