9 Best Sights in Barcelona, Spain

This traditional café and rendezvous point at the top of the Rambla, over the metro station, has an elegant, high-ceilinged interior. The terrace is one of the city's prime people-watching spots—but keep a sharp eye on your bags and valuables.

This house occupies what were once the grounds and buildings of a 14th-century Carthusian convent—though the convent itself is long gone. The present building dates to 1749; it was renovated in 1929 in Catalan Moderniste style, abandoned for a time, and then remodeled in 1980 as part of a large-scale urban improvement project for El Raval, with much of the impressive tile work, brick vaulted arches and stone pillars preserved intact. It now houses the Centre d'Estudis i Recursos Culturals de la Diputació (Center for Cultural Studies and Resources of the Provincial Council) and the Centre de Cultura Contemporània de Barcelona (CCCB: the Centre for Contemporary Culture), in the Pati Manning Espai Cultural—a two-story cloister around a central courtyard (pati means patio or courtyard) with lovely Tuscan arches. The Pati Manning (named for a benefactor of the one-time almshouse) includes a library, a lecture hall and auditorium, and exhibition galleries, and organizes a wide range of cultural and artistic initiatives.

This extraordinary apartment house crowned with an enormous yellow butterfly (papallona) made of trencadís (broken ceramic chips used by the Modernistes to add color to curved surfaces) was built in 1912 by Josep Graner i Prat. Next to Plaça de Espanya, directly overlooking the Arenes de Barcelona (the former bullring, now a multilevel shopping mall), the building displays lines of a routine, late-19th-century design—that is, until you reach the top of the facade.

Gaudí disciple Joan Rubió i Bellver, creator of the Gran Via's Casa Golferichs, won the Barcelona architecture prize of 1913 with this extravagant interplay of decorative brick and white surfaces. The house is traditionally known as El Frare Blanc (The White Monk) for the masía (Catalan country house) that previously occupied the spot and served as home to a community of Dominican monks who wore white habits. Floodlit at night, the building resembles nothing so much as a fairy-tale Andalusian castle. It is not simply a sight to behold: It is also a restaurant, the Asador de Aranda—the venue in Barcelona for oven-roasted milk-fed baby lamb. It was built at the behest of Theodor Roviralta, who made his fortune in the Spanish colonies.

Young scientific minds work overtime in this interactive science museum, just below Tibidabo. Among the many displays designed for children seven and up are the Geological Wall, a history of rocks and rock formations; the digital Planetarium; and the Underwater Forest, showcasing a slice of the Amazonian rain forest in a large greenhouse.

The Ciutadella campus of Barcelona's private Universitat Pompeu Fabra contains a contemporary architectural gem worth seeking out. It's two blocks up from the Ciutadella–Vil·la Olímpica metro stop, just beyond where the tramline out to the Fòrum begins. Once the hydraulic cistern for the Ciutadella waterworks, built in 1880 by Josep Fontseré, the Dipòsit de les Aigües was converted to the school's Central Library in 1999 by the design team of Lluís Clotet and Ignacio Paricio. The massive, 3-foot-thick walls, perforated and crowned with tall brick arches, are striking; the trompe-l'oeil connecting corridor between the reading rooms is a brilliant touch. Even in humble Barceloneta, there are opportunities for really gifted architects to take a historical property in hand and work magic.

You may come up to Tibidabo for the great views, but El Mirador de la Venta has good contemporary cuisine to accompany them.

Barcelona's first public museum, now in its ultramodern new home in the Marisme, displays rocks, minerals, and fossils along with special exhibits on Catalonia and Spain. Kids will go for the hands-on interactive "Living Planet" exhibits and the special collection of venomous beasties. The affiliated Jardi Botànic (botanical garden ), on Montjuic near the Olympic Stadium, boasts a notable collection of species of trees, flowers and shrubs from Australia, South Africa, California, South America, and the Mediterranean.

One of Barcelona's two promontories, this hill bears a distinctive name, generally translated as "To Thee I Will Give." It refers to the Catalan legend that this was the spot from which Satan tempted Christ with all the riches of the earth below (namely, Barcelona). On a clear day, the views from this 1,789-foot peak are legendary. Tibidabo's skyline is marked by a neo-Gothic church, the work of Enric Sagnier in 1902, and—off to one side, near the village of Vallvidrera—the 854-foot communications tower, the Torre de Collserola, designed by Sir Norman Foster. If you're with kids, take the San Francisco–style Tramvía Blau (Blue Trolley) from Plaça Kennedy to the overlook at the top, and transfer to the funicular to the 100-year-old amusement park at the summit.