One of the areas that remained relatively untouched was the underdeveloped western side of Central Park, though some large structures would be erected in the park's remaining empty plots.[142] By 1872, Manhattan Square had been reserved for the American Museum of Natural History, founded three years before at the Arsenal. A corresponding area on the East Side, originally intended as a playground, would later become the Metropolitan Museum of Art.[142][143] In the final years of Central Park's construction, Vaux and Mould designed several structures for Central Park. The park's sheepfold (now Tavern on the Green) and Ladies' Meadow were designed by Mould in 1870–1871, followed by the administrative offices on the 86th Street transverse in 1872.[144] Even though Olmsted and Vaux's partnership was dissolved by the end of 1872,[145] the park was not officially completed until 1876.[146]