Barcelona has several main areas to explore. Between Plaça Catalunya and the port lies the Old City, or Ciutat Vella including El Barri Gòtic (the Gothic Quarter); the shop, bar, and tapas-rich La Ribera (the waterfront, also known as Born-Ribera); the populous central promenade of the Rambla; and El Raval, the former slums or outskirts southwest of the Rambla. Above Plaça Catalunya is the grid-pattern expansion known as the Eixample (literally, the "Expansion") built after the city's third series of defensive walls were torn down in 1860; this area contains most of Barcelona's Moderniste architecture. Farther north and west, Upper Barcelona includes the former outlying towns of Gràcia and Sarrià, the Pedralbes area, and, rising up behind the city, Tibidabo and the green hills of the Collserola nature preserve.
Though built in the mid-18th century, Barceloneta is generally considered part of Ciutat Vella. The Port Olímpic, a series of vast terrace restaurants and discos, is just beyond the Frank Gehry goldfish and the Hotel Arts. The Ciutadella park, once a fortress built not to protect but to dominate Barcelona, is just inland.
A final area, less important from a visitor's standpoint, is Diagonal Mar, from Torre Agbar and Plaça de les Glòries, east to the mouth of the River Besòs. This is the new Barcelona built for the 2004 Fòrum de les Cultures.
