Parc de la Ciutadella. Ciutadella park in Barcelona. Located on site of former citadel and garrison built after fall of Barcelona in 1714 by Felipe V. Later opened to the public in 1877 as a park. Parc de la Ciutadella is Barcelona's oldest, biggest and most popular public park. It is now home to Catalonia Parliament, housed in the former arsenal, and Barcelona zoo occupies a large part of the park. Nearest metro station is Arc de Triomf on Red Line 2