Architect Antoni Gaudí (1852–1926) was a profoundly religious man, and from 1912 forward he made the design of this soaring basilica his life’s work. If it is not the grandest church in all of Spain, it is certainly the grandest constructed within living memory. This “Church of the Holy Family” is a strange and wonderful structure, part retro-Gothic cathedral and part Modernista fantasy, with some bowls of fruit tossed in for color at the tops of the towers. The soaring interior really seems like a place of worship now, after decades as a construction site that stood open to the elements; the roof finally went on a few years ago, and the target date for completion—still almost a decade away—now seems within reach. The massive project was held up by some dramatic roadblocks: The original plans were burnt during the Spanish Civil war, and a grassroots attempt rose to halt the digging of a train tunnel within a few blocks of the basilica, deemed a threat despite seismic studies to the contrary. (The tunnel was dug, and the structure remained upright.) Because Gaudí left the structure unfinished at the time of his death, and his plans went missing, what you see today is a hodge-podge of guesswork by subsequent teams of architects. The west portal (the Façade of the Passion) is especially inharmonious, with clunky white protrusions that look like overgrown Lego blocks. The east façade (of the Nativity), where you will enter, is more in the spirit of Gaudí’s pious Christian view of the New Testament stories, although they appear to have been carved out of volcanic stone, cobwebs, and bat droppings. Dragons and gargoyles hang off corners, and an entire Noah’s ark of preposterous animals (rhinos! elephants!) are carved in stone. And that’s just the outside.

The central nave resembles a gleaming white sci-fi spaceship, although Gaudí’s original intent was to create the illusion of a forest of impossibly tall palm trees, which allow a maximum of light to stream through their fronds from very tall stained-glass windows. And in fact, it is that play of magical light on the walls and floors of the interior that give the Sagrada Familia a true sense of spirituality and earns Gaudí the moniker “God’s architect.” The cost of the elevator ride up the towers, where the true magnificence of Gaudí’s creation is most visible, is absolutely worth the extra euros. Construction of the church came to a near halt at the outbreak of the Civil War and languished until the late 1980s. Yet new construction techniques (and more tourist admissions) have sped up the process. Since the church was consecrated in 2010, the builders have been racing toward a much-publicized projected completion date of the 2026 centenary of Gaudí’s death. (He is buried in the Chapel of Carmel, one level down from the main church.) Buying tickets online in advance has become essential, at least in the busiest seasons, in order to avoid the wait of an hour or more.