on the perimeter wall. Sir William's Dog Run is located to the east of Corbin Drive, south of the overpass over Fort Tryon Drive. The dog run is open 24 hours a day and its regulations allow owners to take their dogs off-leash. Opened in 2001, it is described as the largest dog run in Manhattan. Several trees within Sir William's Dog Run are surrounded by short barriers to prevent damage to their roots. Structures Buildings in Fort Tryon Park include the Cloisters, the gatehouse, a cafeteria and administration building, the field house, and the subway fan house and shed. Except for the Cloisters, these buildings are mostly single-story masonry structures made with ashlar. Numerous other structures also exist, including a gazebo and the Billings Arcade. The Cloisters The Cloisters is a branch of the Metropolitan Museum of Art that houses the museum's extensive collection of medieval European art and artifacts, including the Unicorn Tapestries. The museum's buildings are a combination of medieval structures bought in Europe and reconstructed on-site stone-by-stone, and new buildings in the medieval style designed by Charles Collens. The Cloisters consists of four main cloister structures: Cuxa, Saint Guilhem, Bonnefont, and Trie. The Cloisters also contains three gardens, one each within the Cuxa, Bonnefont, and Trie cloisters. The museum is surrounded by the circular park drive, and its site is bounded by many plantings including an apple orchard to the south and denser vegetation to the north and west. A driveway and a bus stop with Belgian blocks is located at the northeastern portion of the site. The museum was created after John D. Rockefeller Jr. purchased the medieval art collection of George Grey Barnard, and gave it to the Met along with his own collection. Rockefeller, retaining Bernard as an advisor, decided that Fort Tryon Park was the most suitable place for the collection. The Met then had the Cloisters built in Rockefeller's newly created Fort Tryon Park with endowment money from Rockefeller. The Cloisters opened to the public in 1938. A northern extension to the Cloisters, The Fuentidueña Apse, was completed in 1961. Linden Terrace The David Rockefeller Linden Terrace is located at the Promenade's northern end, on the site of Fort Tryon and Tryon Hall. The terrace is located above sea level, the highest location in Fort Tryon Park. It is also the highest landscape feature on Manhattan Island, as measured by the