Seville is Spain’s fourth-largest city, with a population of about 700,000 people. A compact low-rise metropolis, it is a place of vibrant plazas, whitewashed residences festooned with scarlet geraniums and a pedestrian-friendly center that invites exploration. (Although some parts of the city — notably the barrios, with their narrow, winding streets — require good map-reading skills and attention to where you are going.)