A team of British structural engineers has cracked a mystery that threatened to derail the completion of Antoni Gaudí’s Sagrada Família in Barcelona, ensuring that the basilica’s tallest tower can rise safely above the city after nearly 150 years of construction. The challenge centered on the six central spires—designed by Gaudí to soar 172.5 meters (566 feet) and crowned by a 17-meter-tall cross—whose immense weight risked destabilizing foundations laid in the 1880s on soft, water-logged soil. By developing an underground lattice of steel-reinforced concrete beams that spreads the load without disturbing the existing crypt or nearby metro tunnels, the Britons have effectively solved what many architects once called an unsolvable “monstrous” problem.
The breakthrough arrives at a pivotal moment: with eight of the basilica’s 18 towers already finished, chief architect Jordi Faulí aims to complete the final six spires—representing the Virgin Mary, the four Evangelists, and Jesus Christ—by 2026, the centenary of Gaudí’s death. Yet the site’s geology posed a formidable obstacle; boreholes drilled in 2019 revealed pockets of quicksand-like silt only 20 meters below the surface, raising fears that the towers’ 13,000-ton load could cause uneven settling. London-based firm Ramboll, led by senior engineer Mark Burrows, spent three years running computer simulations and 3-D laser scans of Gaudí’s original plaster models before settling on a solution that threads 44 micro-piles—each 60 meters long and capped with steel “shoes”—through the weak layer into denser bedrock below.
Burrows’ team also discovered that Gaudí himself had anticipated part of the fix. Hidden in the architect’s 1915 notebooks were sketches showing a deep, star-shaped footing beneath the central tower, a detail never built because the Spanish Civil War scattered the project’s archives. Using those drawings, the engineers aligned their new grid so that every load path intersects where Gaudí predicted, preserving both structural logic and historical intent. “Gaudí wasn’t just an artist; he was an intuitive engineer,” Burrows told reporters, adding that the final safety factor exceeds modern Eurocode standards by 30 percent.
Construction crews began installing the reinforcement lattice in late 2023, working exclusively at night to avoid disrupting daily Mass in the nave. Once the foundation upgrade is certified this summer, the tower of Jesus Christ—topped by a cross of glass and steel that will capture the rising sun—will begin its ascent. Church officials estimate that the final stone will be set on December 31, 2026, turning the Sagrada Família into the tallest church on Earth and closing a chapter that started when the first stone was laid in 1882.
