The Parc de la Ciutadella sits where a hated fortress once stood — the citadel Barcelona was forced to build, then gleefully tore down. For decades after, this was the city's only green space, and it still feels like its front garden: parliament, museums, a zoo, a lake, and a fountain a teenage Gaudí helped raise.
Three kilometres, an easy morning. Start at the Arc de Triomf — red brick, built to welcome the world to the 1888 fair, not to mark a battle. Walk the palm promenade down to the gates. Inside, bear left for the Castell dels Tres Dragons, Domènech i Montaner's brick pavilion and one of the first true notes of modernisme.
The middle of the walk is the Cascada: Fontserè's monumental fountain, with the young Gaudí on the rockwork. Climb the terrace, then drift to the boating lake — row if you like, or don't. The mammoth statue is worth the small detour.
Finish quietly. The Hivernacle glasshouse, then the plaça before the Parlament, where the Desconsol statue weeps into a still pond. The Arc de Triomf metro is a five-minute walk back the way you came.
