Plaça de Catalunya
Time Out says
Plaça de Catalunya is the largest, most central square in Barcelona. In other words, it’s in the heart of the city: it’s the junction between the Old City and the massive Eixample district, and gives you direct access to some of the city’s most popular streets, including La Rambla, Passeig de Gràcia and Portal de l’Angel. If you go for a stroll at the weekend, you’ll be able to see admire the Fonts Bessones (Twin Fountains) – the two fountains located in the square since 1959 – as they light up in a show of water and colour.
Even though the urbanization of the square started in 1902, it didn’t reach its culminating point until the 1920s, as the Barcelona International Exposition was to take place in 1929. Two years before, a contest open to all citizens was held in order to decorate the square, resulting in 28 different sculptures, such as Josep Clarà’s ‘La deessa’ ('The Goddess'), a nude woman kneeling down that has become one of the city’s symbols. The square was inaugurated by King Alfonso XIII in 1927 and boasts an area of five hectares.
Plaça de Catalunya is also a first-rate shopping area with numerous stores, including the El Corte Inglés department store and El Triangle shopping centre, and has a wide variety of bars and restaurants. This very square is considered Catalonia’s kilometre 0 and therefore is the starting and finishing point of most bus routes. It also has a metro station with access to L1 and L3 lines, and a train station. That being said, if you have a bird phobia, try to avoid any temptation to walk through the centre of that star, as you're likely to be mobbed by pigeons. They're not really known to attack, though.
It's also where you can find a big tourist information centre, the starting point for city bus tours, and a police station.