El Born, Barcelona
First advice: Barcelona in August is very hot, 30 or 35 Cº (as minimum), so do not forget a good hat, sun lotion and bring water always with you. Apart of this, you can find also some summer storms, so do not forget also the umbrella.
The must see places of Barcelona are La Sagrada Familia; Las Ramblas; Passeig de Gracia (Paseo de Gracia in Spanish), where are the famous La Pedrera and Casa Batlló, both of them Gaudí's buildings; Barri Gotic (Barrio Gótico) and Barceloneta beach.
Apart of this, my personal advises are El Palau de la Música Catalana, a wonderful modernist building; Barri de Gracia (Barrio de Gracia) a quartier that was a independent town since it was integrated in Barcelona, but it still preserves his own identity, you can arrive easily by metro, green line, Fontana station; el Barri del Born (barrio del Born) and Barri del Raval, even that if you want to go to the last one is better to do it by day.
About the daytrips, I would advise you going to Montserrat, a mountain that is symbol of Catalunya with a sanctuary at the top; Tarragona with very important Roman ruins; Girona, with an important historic Jewish quartier and Sitges, a cute white town in the beach where, by the way, it's were I live. You can go to all these places by train.
If you have a chance of renting a car, you can go also to the area of La Garrotxa, with towns as Besalú, Santa Pau, Castellfollit de la Roca or Mieres. all of them are medieval and cute little towns that are surrounded of nature, in fact, you can see all of them in one day, as they're very close one of each other. But if you prefer to go to the beach, Cadaqués or Tossa de Mar are very good options. All these places are in Girona's province.
The best way to get these streets is taking Princesa streets or Argenteria st and turn left.. or from Cathedral square you cross the Via Laietana bd and straight .. both options are well .. to the left towards Santa Maria del Mar church or to the right towards Urquinaona and Arc de Triomf monument
The Rivera District is the city's old fishermen neighbourhood. Its narrow streets are very picturesque and,nowadays, are full of bars, restaurants and trendy shops. The main sights are the Carrer Montcada, lined with medieval aristocratic palaces, including the one that hosts the Picasso Museum, and the beautiful church of Santa María del Mar, a typical Catalan Gothic church, whose interior is a true jewel of the Spanish religious architecture: sober, elegant and balanced.
1. Sagrada Familia, just a piece of genius work. 2. Go to Parc Guell, incredible from another planet, bizzare. Roam around El Born, Gotic Quarters and El Ravel. Go to Barceloneta and Olympic area. I witnessed FC Barcelona team members boarding the team bus after practice and saw some of the world's best futbol performers. The Avenida Diagonal has lots of shopping. The Picasso museum is always crowded, but it is interesting in that it is the artists works when he was age 15 to 30.
You have all info about Barcelona public transports here: www.tmb.net (available transports, ticket prices, suggested itineraries...)
You will get good coffee anywhere in Spain. If you like the coffee you get in Canada, ask for "un americano". If you like GOOD coffee, say small, strong with a little milk ask for "un cortado". If you just like a strong black coffee, ask for a "cafe solo".
In the area known as La Ribera, between the church of the Santa Maria del Mar and the wrought iron structure of the Mercat del Born one finds the small Passeig del Born. This little street used to hold glass and tin fairs as well as jousts and tournaments from the 13th to 17th century. Today, take time to wander along this boulevard and its adjoining streets, where bars, shops, and art galleries are plenty.