Barcelona

La Rambla runs for a little over a kilometre from Plaça de Catalunya down to the Columbus column at the old port, a promenade under plane trees between two lanes of traffic. Halfway down, the Boqueria market, officially the Mercat de Sant Josep, fills an iron-roofed hall with fruit, ham, fish and seafood and with counter bars where food is cooked to order; it is calmest early in the morning. Near its entrance a pavement mosaic by Joan Miró marks the Pla de la Boqueria, and the Liceu opera house stands a few steps further down. Off the lower Rambla, the arcaded Plaça Reial, planted with palms, keeps the lampposts Gaudí designed at the start of his career. The crowds are thick from morning into the night, the conditions in which pickpockets work, so bags stay closed and worn in front.

East of the Rambla, the Barri Gòtic is the oldest part of the city, built over the Roman town of Barcino: stretches of the Roman wall survive around the cathedral, and columns of the Temple of Augustus stand in a courtyard on Carrer del Paradís. The cathedral is Gothic inside, behind a façade completed in the late nineteenth century in the Gothic style, and its cloister of palms and fountains keeps thirteen white geese, said to stand for the age of Saint Eulàlia, one of the city's patron saints. Plaça del Rei, closed in by the medieval royal palace and its great hall, the Saló del Tinell, is the entrance to the city history museum, where walkways lead underground through the excavated streets of Barcino. A few streets away, Plaça Sant Jaume sets the City Hall and the Palau de la Generalitat, the seat of the Catalan government, face to face.

West of the Rambla lies El Raval, a dense old quarter of narrow streets and small shops, opened up in its middle by the palm-lined Rambla del Raval. Just off the Rambla on Carrer Nou de la Rambla, Palau Güell is the town mansion Gaudí built in the late 1880s for his patron Eusebi Güell: a central hall rising through the house to a parabolic dome, and a roof of chimneys clad in broken tile. At the quarter's northern end, MACBA, the museum of contemporary art, fills a white building by Richard Meier on Plaça dels Àngels, with the CCCB cultural centre beside it.

North-east of the cathedral, across Via Laietana, the quarter of Sant Pere holds the Palau de la Música Catalana, Lluís Domènech i Montaner's concert hall for the Orfeó Català choir, finished in 1908. Its brick front is set with mosaic columns and sculpture, and the hall inside is lit by a stained-glass skylight that hangs from the ceiling like an inverted dome. It is seen on a guided tour or, better, from a seat at a concert. A few streets south, the Santa Caterina market works under a wavy roof of coloured ceramic tiles, a neighbourhood market where the quarter does its shopping.

South of Santa Caterina, El Born gathers around Santa Maria del Mar, the church of the old waterfront quarter, built in the fourteenth century in a little over fifty years, which gives it a rare unity: a wide nave, slender octagonal columns and plain stone walls under a great rose window. Close by, Carrer de Montcada is lined with the palaces of medieval merchants, several of which house the Picasso Museum, strongest on the painter's youth and early years and holding his series of variations on Velázquez's Las Meninas. Passeig del Born leads from the church to the iron hall of the old Born market, where the excavated streets of the early eighteenth-century quarter lie under the roof.

East of El Born, the Parc de la Ciutadella is the old town's park: a boating lake, palms, an old glasshouse and a shade house, and the Cascada, a monumental fountain crowned by a gilded chariot. The Parliament of Catalonia and the city zoo stand within its grounds. The park held the Universal Exhibition of 1888, and the exhibition's gateway, the brick Arc de Triomf, stands at the far end of Passeig de Lluís Companys, the broad promenade that leads to the park from the north-west.

At the foot of the Rambla, the Columbus column marks the start of Port Vell, the old harbour, where the Rambla de Mar, a wooden footbridge, crosses to the quay of the aquarium, and a palm-lined promenade follows the water toward Barceloneta. Barceloneta itself, laid out in the mid-eighteenth century on a triangle of land between the harbour and the sea, is a grid of narrow streets and tall, slim houses with washing on the balconies, gathered around a small market. Its bars and restaurants are the place for seafood and rice dishes, and its streets run down to the beach.

From Barceloneta, the Passeig Marítim runs north-east behind a chain of beaches — Sant Sebastià, Barceloneta, Somorrostro, Nova Icària, Bogatell, Mar Bella — some 4.5 kilometres of sand in all, laid out when the seafront was rebuilt for the 1992 Olympic Games. Frank Gehry's golden fish sculpture rises over the Port Olímpic marina at the foot of the Olympic Village's two towers. The beaches nearest the old town fill first; Nova Icària, Bogatell and Mar Bella, further along, are calmer and close to stations on metro line 4. The sea is warm enough for most swimmers from June into October, at about 25°C in August.

North of Plaça de Catalunya, the old town gives way to the Eixample, the extension built from 1860 to the plan of Ildefons Cerdà: a grid of square blocks with their corners cut at an angle, so that every crossing opens into a small octagonal space. Its streets hold much of the city's modernista architecture, with ornate doorways, tiled hallways and carved balconies far beyond the famous houses. Rambla de Catalunya, a tree-lined promenade one street west of Passeig de Gràcia, is the calmer walk through it, and on the Eixample's western side the Sant Antoni market, restored to its nineteenth-century iron hall, is a neighbourhood food market with bars all around.

Passeig de Gràcia is the Eixample's grand avenue. On the block between Carrer del Consell de Cent and Carrer d'Aragó, three modernista houses by three architects stand almost side by side: Domènech i Montaner's Casa Lleó i Morera on the corner, Puig i Cadafalch's stepped-gabled Casa Amatller and Gaudí's Casa Batlló, remodelled with a façade of coloured glass and ceramic, balconies like masks and a roof that curves like a dragon's back. A few blocks up, on the corner of Carrer de Provença, Gaudí's Casa Milà, known as La Pedrera, the stone quarry, wraps the corner in a rippling stone front with balconies of twisted iron. Both houses are visited inside, and at La Pedrera the visit ends on the rooftop among sculpted chimneys and stairwell towers.

In the north of the Eixample, the Sagrada Família is a church still being built. Begun in 1882, it passed to Gaudí the following year and became his life's work, and he is buried in its crypt. The Nativity façade on the east side, thick with carved figures, is the part largely built in his lifetime; the Passion façade on the west carries Josep Maria Subirachs's stark, angular sculpture, and the main façade is still under construction. Inside, columns branch like trees toward the vaults, and the stained glass throws blues and greens across the nave in the morning and reds and oranges in the late afternoon. Entry is by a timed booking made ahead, the towers are climbed on a separate ticket, and the metro station of the same name stands beside the church.

From the Sagrada Família, Avinguda de Gaudí runs diagonally to the Hospital de la Santa Creu i Sant Pau, which Domènech i Montaner built in the early twentieth century as a garden city of pavilions, with brick fronts rich in mosaic and sculpture, roofs and domes of coloured tile, and underground passages between them. No longer a hospital, its restored pavilions are open to visitors, and the ensemble is listed by UNESCO together with his Palau de la Música Catalana.

Above the Diagonal, at the top of Passeig de Gràcia, Gràcia was a town of its own until Barcelona absorbed it in 1897, and it keeps a village scale: narrow streets of low houses opening into small squares such as Plaça del Sol, Plaça de la Virreina and Plaça de la Vila with its clock tower, ringed with bar terraces that fill in the evening. Carrer Gran de Gràcia is its main street. For a week in mid-August, at the Festa Major de Gràcia, neighbours decorate whole streets to themes of their own making, each street competing with the next.

On the slope of the Carmel hill above Gràcia, Park Güell was laid out by Gaudí from 1900 as a garden estate for wealthy households; few houses were built, and it became a public park. Its monumental zone is entered on a timed booking made ahead: two gatehouses with roofs of broken tile, a stair guarded by a mosaic lizard, a hall of columns, and above it a terrace edged by a long, winding bench covered in coloured ceramic, with the city and the sea beyond. Paths climb from there through the wooded upper park to the Turó de les Tres Creus, a rocky top crowned with stone crosses. From Lesseps or Vallcarca on metro line 3, the approach is a steep walk uphill.

Montjuïc rises over the port on the south-western edge of the centre. From Plaça d'Espanya, an avenue lined with the fountains of the 1929 International Exhibition, then steps and outdoor escalators, climb to the Palau Nacional, home of the MNAC, the national art museum of Catalonia: its Romanesque rooms hold apse paintings removed from churches in the Pyrenees, among them the Christ in Majesty of Sant Climent de Taüll, and the terrace in front looks over the city. A few minutes' walk away stand the Barcelona Pavilion, a reconstruction of Mies van der Rohe's German pavilion of 1929, and Poble Espanyol, a village of copies of buildings from all over Spain. Higher up, the Fundació Joan Miró shows the artist's paintings, sculpture and tapestries in a white building by Josep Lluís Sert, near the Olympic Ring and the stadium of the 1992 Games, and the castle on the summit looks down on the harbour. A funicular climbs from Paral·lel metro station to the middle of the hill, and Poble-sec, at its foot, is a quarter of small bars along Carrer de Blai.

Behind the city, the Collserola hills form a natural park of pine and oak woods. Tibidabo, at 512 metres their highest summit, carries the Temple of the Sacred Heart and an amusement park, and the view from the top runs across the whole city to the sea; the slender Torre de Collserola, a telecommunications tower by Norman Foster, stands on the ridge nearby. Below the summit, the Carretera de les Aigües, a level track along the hillside, makes a walk or a run with Barcelona laid out beneath it. The FGC suburban line from Plaça de Catalunya and the Vallvidrera funicular climb into the hills.