Lampposts in Plaça Reial, Barcelona

Plaça Reial's six-armed lampposts, Gaudí's first official commission from Barcelona City Council, designed in 1878 when he had barely left architecture school. Look up at the top: a winged helmet of Mercury, the Roman god of commerce, with snakes coiling around the shaft below it in a nod to his caduceus. The red ironwork against the square's palms is free to see at any hour, a good first stop on a walk down La Rambla.