Montjuïc is the reason old Barcelona is the colour it is: the cathedral, Santa Maria del Mar and the sea walls were cut from this hill's yellow-grey sandstone. Low and flat-topped, it stands between the city and its port, and for centuries it worked as quarry, lookout and fortress — the star fort rebuilt on the summit from the 1750s still sits behind dry moats. Then Barcelona turned the slope into a stage: the 1929 world's fair terraced it with palaces, staircases and Carles Buïgas's Font Màgica, and the 1992 Olympics gutted the stadium above and rebuilt it inside its 1929 shell.
Today it is one long sloping park with museums folded into it. You walk from cactus terraces hanging over the container cranes into shaded gardens where water runs down a tiled stair, past Miró's white foundation and the Romanesque church murals of the MNAC. The air smells of pine and dust, and gulls come up off the harbour. On the nights it runs, the fountain becomes the main event on the hill: thousands of jets rise, fold and change colour in time with music, the crowd banks up the steps below the floodlit Palau Nacional, and the rest of the hill stays dark above them.