Plaça de Catalunya is a large square in the city centre in Barcelona, it is considered to be the city centre and where the old city and the Eixample area starts. the square is the centre for any barceloní of origin or expat living in the city, is the place of gathering and is where most of people meet.
Some of the city's most important streets meet in Plaça Catalunya, such as Passeig de Gràcia -high end street-, Rambla Catalunya full of restaurants and shops, or the mytic La Rambla that goes down to the sea side.
The square is famous for its fountains and statues and being very near the most popular attractions in town, the square occupies an area of 50,000 square metres.
One of the typical things to do in Plaça Catalunya and I use to do with my granpa when I was little, was to go to the square and buy food for the pidgeons called "veces" and you can buy them in little bags in the same Plaça. Nowadays, it might not be a popular thing to do and pidgeons have bad press, but back in the 90s all children in town used to do that at least once a year.
After the medieval walls of Barcelona were demolished in the 19th century, there were projects and designds to conveive the new urban spaces. Plaça Catalunya was part of the Rovira plan in 1859, and it was urbanized in the end in 1902. Taking advantage of the Internations Exhibition in 1929 in Barcelona, they projected as well the metro station in the square.
I would like to mention two places in the square that are typical places to meet, if someone meets in the centre most likely they will meet in a landmark in the square. The three main landmarks are: the Zurich café, the Hard Rock Café and the Apple store, the oldes one as a tradition to meet there would be the Zurich as it is located right in front of the metro station and it is convenient to meet there. If you pass by you will see dozens of people waiting for someone and if you are meeting with locals it is a frequent point of meeting. Same story with the hard rock, it is in one side of the street, it is visible and known enough so everyone can find it easily.
The apple store is a new meeting point and you will see plenty of people with their mobile and pc devices getting free wifi from the store and since it has become an institution not only in Barcelona but in many parts of the world, it is a meeting place too for youngsters.