Barceloneta: 7 Portes

Passeig Isabel II 14
+34 93 319 30 33
"1 p.m. to 1 a.m., uninterrupted" is written across the front door of this restaurant, the oldest in Barcelona. While it is among the best fish joints, 7 Portes does well to advertise its most salient feature in a city where it is gauche and nigh impossible to eat early. Popular "rich man's paella," is so dubbed because the chef has shelled the lobster, mussels, and clams. The dining rooms are divided into smoking and non-smoking, which breaks down into locals and visitors, pleasure and business, respectively. Famous guests have included Pedro Almodóvar, Salvador Dalí, and Orson Welles.
Dress: Casual
Prices: Moderate to expensive
Reservations: During peak hours

Ciutat Vella: Ca L'Isidre
C/Les Flors 12
+34 93 441 11 39
Ca L'Isidre is the grand dame of Barcelona cuisine, serving Catalan favorites like morcilla (blood sausage) and lamb brains in black butter as well as less advanced options. The menu changes daily, depending on what the chef finds in La Boqueria, Ciutat Vella's iconic market. The stately restaurant has only 50 seats, and solo diners are tucked into a nook at the front. (The restaurant has 50 seats, the nook four.) Service is highly professional, down to the ritual of cutting and lighting the after-dinner cigar. El Raval may have been a more salubrious part of town when the restaurant opened in 1970; these days it is wise to take a taxi.
Dress: Fashionable
Prices: Expensive
Reservations: Recommended

Montjuïc: Oleum
Parc de Montjïuc, Palau Nacional
+34 93 289 06 79
Located in the National Art Museum of Catalunya, this three-year-old restaurant has created more buzz for the institution than its Romanesque collection. It has soaring multicolored marble walls, and an angled overhead mirror reflects the stunning hilltop view back at the well-heeled lunchers (dinner is by prearrangement for groups only). The food is an upscale version of menu del día, prescribed by Franco to ensure a filling midday meal with wine for workers. Along with a stray foam or two, the English-language menu sports some charming clunkers like "cream of gourd with artichokes to the rosemary and creaking of ham"—a winner, by the way.
Dress: Business/business casual
Prices: Moderate
Reservations: Not necessary

L'Eixample: Paco Meralgo
C/ Muntaner 171
+34 93 430 90 27
This minimalist bar has everything that is fun about tapas—a wealth of choice, energetic crowd, bantering waiters—while eliminating intimidating elements with an English menu and balanced gender ratio (Barcelona tapas bars are often dominated by older men). Be prepared for conversation here—your neighbors won't be shy with suggestions. Must-trys include the potato bomba and raw cod salad. An elderly customer took pains to explain that the Catalan custard, an eggy crème brulée, is actually a local invention. "The French stole it!"
Dress: Casual
Prices: Inexpensive
Reservations: Not necessary