Every Thursday at noon, a group of farmers and irrigators gathers at the Gothic doorway of Valencia's Cathedral — the Puerta de los Apóstoles — to settle water disputes the same way their predecessors have done since the 10th century: standing, speaking, and leaving without a single written record. The Tribunal de les Aigües is the world's oldest functioning court, and it is entirely unremarkable to most people walking past. That gap between what's visible and what's actually happening is exactly what makes Valencia one of Spain's most rewarding cities to explore properly. Founded by the Romans in 138 BC, shaped by eight centuries of Moorish ingenuity, and now home to a futuristic skyline designed by a local architect, Valencia layers civilisations on top of each other with almost reckless generosity. This guide cuts through the generic "paella and beach" narrative to show you the city's real depth — its underground ruins, its contested cathedrals, its fire festivals, and the local rituals that haven't changed in a millennium.