Tourism accounts for much of Uruguay's economy. Tourism in Montevideo is centered in the Ciudad Vieja area, which includes the city's oldest buildings, several museums, art galleries, and nightclubs, with Sarandí Street and the Mercado del Puerto being the most frequented venues of the old city. On the edge of Ciudad Vieja, Plaza Independencia is surrounded by many sights, including the Solís Theatre and the Palacio Salvo; the plaza also constitutes one end of 18 de Julio Avenue, the city's most important tourist destination outside of Ciudad Vieja. Apart from being a shopping street, the avenue is noted for its Art Deco buildings, three important public squares, the Gaucho Museum, the Palacio Municipal and many other sights. The avenue leads to the Obelisk of Montevideo; beyond that is Parque Batlle, which along with the Parque Prado is another important tourist destination. Along the coast, the Fortaleza del Cerro, the Rambla (the coastal avenue), 13 kilometres (8.1 mi) of sandy beaches, and Punta Gorda attract many tourists, as do the Barrio Sur and Palermo barrios.