Green finalized the negotiations to purchase the northernmost of the park which was later converted into a "rugged" woodland and the Harlem Meer waterway. When the American Civil War began in 1861, the park commissioners decided to continue building Central Park, since significant parts of the park had already been completed. Only three major structures were completed during the Civil War: the Music Stand and the Casino restaurant, both later demolished, and the Bethesda Terrace and Fountain. By late 1861, the park south of 72nd Street had been completed, except for various fences. Work had begun on the northern section of the park but was complicated by a need to preserve the historic McGowan's Pass. The Upper Reservoir was completed the following year. During this period Central Park began to gain popularity. One of the main attractions was the "Carriage Parade", a daily display of horse-drawn carriages that traversed the park. Park patronage grew steadily: by 1867, Central Park accommodated nearly three million pedestrians, 85,000 horses, and 1.38 million vehicles annually. The park had activities for New Yorkers of all social classes. While the wealthy could ride horses on bridle paths or travel in horse-drawn carriages, almost everyone was able to participate in sports such as ice-skating or rowing, or listen to concerts at the Mall's bandstand. Olmsted and Vaux were re-hired in mid-1865. Several structures were erected, including the Children's District, the Ballplayers House, and the Dairy in the southern part of Central Park. Construction commenced on Belvedere Castle, Harlem Meer, and structures on Conservatory Water and the Lake. 1870–1876: completion The Tammany Hall political machine, which was the largest political force in New York at the time, was in control of Central Park for a brief period beginning in April 1870. A new charter created by Tammany boss William M. Tweed abolished the old 11-member commission and replaced it with one with five men composed of Green and four other Tammany-connected figures. Subsequently, Olmsted and Vaux resigned again from the project in November 1870. After Tweed's embezzlement was publicly revealed in 1871, leading to his imprisonment, Olmsted and Vaux were re-hired, and the Central Park Commission appointed new members who were mostly in favor of Olmsted. 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. By 1872, Manhattan