Gràcia, about 1 km north of the centre of Barcelona at the north end of the Passeig de Gràcia, is the most distinctively Catalan neighborhood to be found in easy walking distance of the center. A prosperous neighborhood, Gràcia nonetheless has more a local than a cosmopolitan feel to it, with much of life lived on the many public squares.
It's also a very good place to start (or finish) a walk through the most important modernist buildings.
A good place to stay in an hotel.
Both the Fontana and the Lesseps Metro stations (on line L3) are located in or near the Gracia district. From the stations, the heart of Gracia will be to the NNE (this may appear as East or "to the right" on most, if not all, maps of Barcelona).
Check out any plaza and it will most likely be humming with life and vibrancy.
Güell Park (Parc Güell), . This is on a hill overlooking Barcelona, so expect a relatively steep walk to the top (Lesseps metro station, then follow arrows that are every 300 m; you will be rewarded with a panoramic view of the whole city. For more off the beaten track, the park can be also reached from metro Vallcarca. The park has two distinct parts, a relatively undeveloped (and uncrowded) natural area near the top of the hill, and the more famous sculpture park below (really crowded most of the time). The sculpture portion is full of walkways and other structures exhibiting the distinct and colorful style of Gaudi, including the famous terrace. The undeveloped part is isolated(?) from the sculpture park with a fence. If you take the bus 24,you sure to enjoy the nice people around you .8€. edit
Prosperous private villas can be found above the Guell Park.
Casa Vicens, C/de les Carolines 24 (buses 22, 24, 31, 32), . The first building Gaudi himself built in Barcelona. Can be seen only outside, as it is a property of a private owner. The only exception is May 22 every year, when it is open to "neighbours and citizens". In UNESCO World Heritage Sites list since 2005.edit
One of Barcelona's most lively festivals, the Festa Major de Gracia, is a week long festival that displays the best of Catalan with a mass celebration in the streets. One of the most popular events is the 'Best decorated street', where residents from 23 neighboring streets use anything and everything to decorate their street in a theme and vie for the prize.
Hibernian (Secondhand English Bookshop), Carrer Montseny 17 (Metro Fontana), ☎ +34 932 174 796, . 10:30 AM to 8:30 PM. Good selection in many categories. Also has some new books, and a shelf of German and French titles.Most used paperbacks at €5. edit
Vinçon, Passeig de Gracia 96 (M. Diagonal), ☎ (93) 215-6050, . Mon-Sat 10AM-8:30PM. This is a place modern design lovers simply must visit. Offers everything from little household objects to furniture in a sleek and contemporary design--and much beyond interior decoration.edit
Kelkom. Street Còrsega 393. Between Bruc and Girona Street. Metro L5 Verdaguer or L3 Diagonal. Shop of gifts and accessories where you can find necklaces, earrings, bracelets, shirts, bags, clocks, gifts etc., of different styles and prices.
Most of the luxury international brands can be found at Passeig de Gracia.
Breton. Located just across the street down an "alley" from the Fontana metro station. An assortment of pictures out front of the restaurant give diners an idea of the plates as well as a tacky feel, but inside the restaurant is clean and simple. Good service and decent food make this a place to possibly frequent because you know what to expect. A menu del dia and a great menu to select from. "Normal" to Moderate prices. Menu del dia ~€10, Bocadillos ~€4, salads/"entrees" ~€3.
Restaurant Petra Carrer D'Asturies. Authentic Lebanese cuisine in the heart of Gracia. This great pedestrian street has several restaurants and many shops, but Petra offers traditional Mediterranean dishes. Shwarma, falafel, hummus, traditional pita and much more. Takeout available. Combination Plates ~€10.
Veg World, C/Bruniquer 26 (Take the left from Joanic Metro station and walk for 5 min. The restaurant is on the left side of the street.), ☎ +34 93 210 70 56 (firstname.lastname@example.org). Tues to Sat 12:45PM to 4PM & 8PM to 11PM, Sun 12:45PM to 4PM, closed Monday. A restaurant that serves only vegetarian food - mainly Indian dishes. This may be the only place in Barcelona where you can get Masala Dosa.05-15€. edit
Can Xurrades, Carrer Gran de Gracia, 57, ☎ 93 217 30 97, . Closed Sunday (all-day) and Monday night. Probably one the best Catalan restaurants in the neighborhood, although their selection of other Spanish food is quite good. Particularly excels at meat dishes, cooked in traditional Catalan style. Dishes of note include the Ous Estrellats (Andalusian scrambled eggs with potato) as well as desserts such as strawberries with salt and pepper. Great wine selection with various Catalan varieties.edit
Flash-Flash C/Granada del Penedès, 25. Not really in Gràcia, but next to it, it's one of the restaurants of the Tuset street years, when the Gauche Divine was the cool group in the city. This restaurant was made as a cool bar during the late 60s and it remains unchanged. The food's good (omelettes is the speciality and the cheapest option). About €15.
Taverna El Glop, Sant Lluís, 24 (intersection of Sant LLuís/Montmany), . Catalan meals. Allow about €20 per person, although you could get out of there for half of that if you let the price dictate your choice of dishes. See chain review in the Eat section of Barcelona.edit
Origen 99.9%, C/Ramon y Cajal 12, ☎ +34 93 213 60 31 (email@example.com), . 12:30PM-1AM Mon-Sun ('''no break for siesta'''). Eco-friendly chain of Catalonian-cuisine restaurants; organic only in some of products. Good choice of specialty liquors.main courses: fish €5.5-6; meat: 5.85. edit
La Porteria La Forja, 11. This quiet street holds a few bars and restaurants to choose from. La Porteria is nothing fancy, but seems to keep a steady local crowd. They have a menu del noche (like the menu del dia), which provides a good value and (what I assume was) the proprietor served his own wine from the "Ribera" (del duero) region of Spain. The selection of 3 olive oils with bread before the meal was a pleasant bonus. Menu del noche - ~€22.
La Taberna del Cura (The tavern of the priest), Carrer Gran de Gracia, 83. Known by locals as one of the better restaurants in town, the menu is mostly meat selections, but seafood can be ordered from it's sister restaurant Botafumeiro next door. La Taberna is on the expensive side, but the food is excellent.1st courses €4-12, main courses €12-20. (salad, filet, small bottle wine, water, dessert, coffee - €50). edit
Alkimia, Carrer Industria 79. One of Barcelona's most highly regarded restaurants, run by acclaimed restauranter Jordi Vilà. With a minimalist white interior that directs the attention to the inventive and indulgent foods on offer, Alkimia spearheads a new wave of new Catalan cooking that will delight and impress. Was awarded a Michelin Star.
Botafumeiro Carrer Gran de Gracia, 83. The sister restaurant (and next door) to La Taberna Del Cura, Botafumeiro specializes in seafood, while La Taberna handles the meats. High quality food with a price tag to match.
Gracia is popular among students, and offers a lot of nice restaurants and bars for the student budget. The plazas in the area, as Plaça de Sol for instance, are filled with nightlife.
El Dorado, Plaça del Sol, 4. With an ample dance floor, it also has a pool table, 'futbolín' and arcade games. The giant video screens and the monitors over the bar are other icons of this Music Bar. Drinks are catered for by staff that are professional, likeable and friendly.
Eldorad2, in the street Ramis, 2-4 (between Milà i Fontanals and Quevedo, 2 streets below Travessera de Gràcia, next to the Plaça John Lennon). A recently opened subsidiary of El Dorado Bar that shares the principles of quality and service of the main house.
Bar Bambo LaForja, just off via Augusta. Small local bar with a clean, cozy atmosphere and a single dart board. Turntables behind the bar control the mix of music which is a variety of American and Spanish upbeat hits. Estrellas - €2.
Places to seek more bars:
Plaça del Sol Has a lot of bars, such as Sol Soler, Woody's
Plaça Rius i Taulet This nice square with the old city hall and the clock tower in the middle has also many bars.
Plaça de la Revolució Is not as crowded as the others, but has an Ice cream bar, owned by two Italian sisters, that serve the best ice creams in Barcelona. The problem is that you may have to wait a long time.
BBB - Jardinets Guest House, Carrer Gran de Gracia, ☎ +34 644 200 680 (firstname.lastname@example.org), . The beautiful building breaths the atmosphere of the late 19th century, which also is reflected in the inside. You'll find it relaxed and well preserved. Free access to the fridge, microwave and all the ingredients to prepare yourself a varied Mediterranean-style breakfast.From €50/double room / breakfast and WiFi included. edit
Barcelona City North, . Three stops by metro away from Catalunya square. Bathroom ensuite, tv, satellite, air-conditioned, WiFi.
Pensión Norma, up 3 flights of stairs at C. Gran de Gràcia, 87, Tel. (+34) 237 44 78. Modest rooms, some with bath, about a kilometre north of the centre of town. About €25 per night.
Barcelona apartment rental is the best and most affordable way to enjoy the city of Barcelona.It  offers you a great collection of apartments to rent in Barcelona within your budget, so that you are burdened with accommodation rates. All our accommodations are located in the best spots of the city which will enable you to enjoy your holiday or business trip to the highest extension.
NH Belagua, Via Augusta 89-91, ☎ +34 932 373 940 (email@example.com), . Rooms with double windows to keep out street noise. Like many European hotels, neighbor rooms can still be heard. Moderate to expensive in price, probably geared more towards the business traveler. Great continental buffet breakfast included with room.€140. edit
Hotel Sagrada Familia Apartments, Calle Napoles 8, . The modernist building that houses the apartments is situated footsteps away from the Sagrada Família, the apartments enjoy an excellent location and quality features.edit