What makes La Sagrada Familia the greatest modern building on the planet

Last year nearly 4.9 million people visited La Sagrada Familia - Guillermo Martinez

To visit Barcelona’s soaring Sagrada Família basilica is to visit a parallel universe in which architectural modernism barely happened, symbolism and decoration remained acceptable and we kept creating places with joy, natural patterns and a whiff of the sacred.

The 144-year-old construction site also offers a 21st-century glimpse of the medieval era, where whole lifetimes were spent in the shadow of great churches, towers and steeples inching slowly towards the heavens. Florence Cathedral took 140 years to build. Toledo’s took 267 years. La Sagrada Família, designed by the great Catalan architect Antoni Gaudí, was started in 1882; 144 years later, they are still building it – a continuous bridge spanning our present with the lives of our great-great-grandparents.

The Sagrada Família Foundation recently completed the 163m central Torre de Jesús (Jesus Christ Tower), an achievement that will be marked by the visit of Pope Leo XIV, who is inaugurating the tower on June 10 – one century to the day since Gaudí’s death. But they are not finished. The Façana de la Glòria (Glory Façade), depicting eternal life and set to be the basilica’s most elaborate entrance, requires another decade.

The basilica’s soaring central tower was completed in October 2025 - Emilio Morenatti

La Sagrada Família is to Barcelona what Notre Dame and the Eiffel Tower combined are to Paris: simultaneously church and state, sacred space and secular symbol, God’s house and the city’s icon. Begun as a conventional Gothic church in a Latin cross shape by Francesco del Villar, who quickly resigned, it was transformed by Gaudí into one of the world’s most ambitious and recognisable buildings. It is not a cathedral, though most visitors assume that it is. It combines Gothic aspiration, Christian symbolism, Catalan craft and forms drawn from nature. Columns branch like trees. The stone seems to grow. The building’s high nave rises as a forest of tapering trunks reaching towards the canopy of light.

An engineering high-wire act

I was fortunate enough to be shown around by the church’s lead architect, Jordi Faulí, a quiet man in a proper suit, with a well-thumbed book of Gaudí’s drawings bulging from one pocket (a scale model nestles in another). With his team of 10 designers, Faulí is overseeing a building of global significance. He is therefore one of the world’s most consequential living architects. Yet few know his name. You will seek in vain for any recent reference to him in the British architectural press. As we thread our way between the pressing crowds, none of the thronging tourists recognise him or spare us a second glance.

Writer Nicholas Boys Smith was given an inside look at the ongoing construction of the Sagrada Familia - James Breeden

As a child in the Catalan countryside in the 1850s, Gaudí had a sharp eye for nature and the everyday. Faulí explains, as we walk through the nave, that the church’s tricks all derive from close natural observation. Studying trees and Gothic cathedrals, experimenting for a decade with string-hung weights, Gaudí evolved a new system of parabolic arches and arboreal columns with trunks, nodes like tree knots and higher “branches” spanning out to support the roof.

The result is breath-catching. A forest of 52 columns, one for each Sunday of the year, holds up the high roof with no flying buttresses, despite its immense height. Their lower parts are made from different stones according to the weight they bear: Montjuïc sandstone in the side naves, granite in the central nave, basalt around the crossing and red porphyry for the four great central columns.

Above the building, Gaudí planned 18 towers: 12 bell towers representing the apostles and six taller central towers representing Jesus Christ, the Virgin Mary and the four Evangelists. Only four remain unbuilt. The church’s 16 central columns carry the six immense towers that now dominate Barcelona’s skyline. This is an engineering high-wire act of space-age ambition, all evolved by a model-building recluse in a workshop without computers or calculators.

Connecting heaven and earth

Light, curves and colour are everywhere. Hyperboloid skylights lined with reflective glass scatter sky through the ceiling just as light penetrates through the leaves of a forest. The east-facing Façana del Naixement, or Nativity Façade, is a rainforest in stone, brimming with fronds and faces, people and palms seemingly woven into the building. Tourists stare, stupefied. I don’t blame them. When it first emerged from its scaffolding in November 1925, Gaudí asked his workmen, “Don’t you think it joins heaven and earth?” One, open-mouthed, replied, “fa goig” – “it’s beautiful”.

The Sagrada Familia’s 18 towers stand at various heights, with the tallest being 172.5m high - James Breeden

Climb up into the towers. Endless decoration peeps out, otherwise visible only to drones, birds and, as with medieval cathedrals, to God. The towers are a chequerboard of different stones and of lozenge-shaped windows. They are not cuboids or pyramids like most medieval steeples but tall, tapering and honeycombed as if Gothic towers had grown from the soil rather than been drawn by hand.

The textured surfaces with their patterned stone incisions recall an extended pigeon coop. Swallows and house martins agree. They have colonised the towers, flashing in and out of the hundreds of holes, skimming and sweeping around the basilica’s roofs and windows. Gaudí’s design was premised on nature. A century after his death, nature has made itself at home.

Patterned stone, honeycombed steeples, and colourful decoration adorn Gaudi’s cathedral - James Breeden

Gaudí was a paradox of a man, a radical who was also a reactionary, a supposed harbinger of architectural modernism who was also profoundly Catholic. A delicate dandy in his youth (his brother wore his shoes in for him) he evolved into an ascetic recluse. Photos of him in old age are rare, so effectively did he shun publicity.

Appropriately for a Catalan conservative, Gaudí came from a family of metal workers, one of the great craft traditions of Barcelona. Four generations had forged iron. His family home was even called Mas de la Caldera, Cauldron Maker’s House. Some of the basilica’s metalwork, for example the iron net meshing around the central column of the Nativity Façade, was wrought by his own hands. You can touch it as you walk past, placing your hand where Gaudí once felt the cooled metal.

For the people

“Ornament”, wrote the Victorian writer John Ruskin, “is the origin of architecture”. Gaudí agreed. The 20th century did not. George Orwell described La Sagrada Família as “one of the most hideous buildings in the world”. Barcelona’s intelligentsia long criticised it as a waste of funds – ironically for a church that now earns €150m in tourist income every year, funding its own construction. The art critic Robert Hughes called the church a “cliché” and “rampant kitsch”.

The people disagree. Something about La Sagrada Família’s mix of faith, symbolism and modernity clearly touches the public. It is Spain’s most visited monument. Last year nearly 4.9 million came: modern-day pilgrims, some reverently and self-consciously Catholic, others less coherently seeking revelation via selfie sticks and Instagram. Patterns of human behaviour are unchanging. Tourists are banned from some portions of the city’s Gaudí buildings due to their propensity to pry off chips or strip tiles, like medieval pilgrims at a saint’s tomb. We covet what we revere.

Tourists flock to Barcelona to marvel at the cathedral’s architecture - James Breeden

One reason tourists come to stare is, doubtless, that they have been told they should. But that is not all. Gaudí’s basilica really is that overused word, “unique”. Every city has a cathedral. Only Barcelona has La Sagrada Família. Only here can we tread in an alternate reality unafflicted by the catastrophe of “traffic modernism” which has ruined our cities for a century, and where traditional design just kept on going.

When Gaudí lay dying, he refused to be moved to a posher and more expensive hospital. “Here is where I belong,” he whispered, “among the poor.” Gaudí would doubtless side with the public, not the elites, in defence of the church which he caused to exist and which, alongside Jordi Faulí and his team, he is still building posthumously, a century after his death. Perhaps he would cite St Thomas Aquinas, whose writings influenced him: “Pulchrum est quod visum placet” – “Beauty is that which gives pleasure when seen.”

Nicholas Boys Smith is founder and chairman of Create Streets and a visiting professor of architecture at the University of Strathclyde.

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