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. 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. Even though Olmsted and Vaux's partnership was dissolved by the end of 1872, the park was not officially completed until 1876. Late 19th and early 20th centuries: first decline By the 1870s, the park's patrons increasingly came to include the middle and working class, and strict regulations were gradually eased, such as those against public gatherings. Because of the heightened visitor count, neglect by the Tammany administration, and budget cuts demanded by taxpayers, the maintenance expenses for Central Park had reached a nadir by 1879. Olmsted blamed politicians, real estate owners, and park workers for Central Park's decline, though high maintenance costs were also a factor. By the 1890s, the park faced several challenges: cars were becoming commonplace, and with the proliferation of amusements and refreshment stands, people were beginning to see the park as a recreational attraction. The 1904 opening of the New York City Subway displaced Central Park as the city's predominant leisure destination, as New Yorkers could travel to farther destinations such as Coney Island beaches or Broadway theaters for a five-cent fare. In the late 19th century the landscape architect Samuel Parsons took the position of New York City parks superintendent. A onetime apprentice of Calvert Vaux, Parsons helped restore the nurseries of Central Park in 1886. Parsons closely followed Olmsted's original vision for the park, restoring Central Park's trees while blocking the placement of several large statues in the park. Under Parsons' leadership, two circles (now Duke Ellington and Frederick Douglass Circles) were constructed at the northern corners of the park. He was removed in May 1911 following a lengthy dispute over whether an expense to replace the soil in the park was unnecessary. A succession of Tammany-affiliated Democratic mayors were indifferent toward Central Park. Several park advocacy groups were formed in the early 20th century. To preserve the park's character, the citywide Parks and Playground Association, and a consortium of