Sagrada Família: How Gaudí's Dream Became the World's Longest Construction Project

Started in 1882 and still rising today, Sagrada Família is the world's longest-running construction project — surviving Gaudí's death, a civil war, and lost blueprints, only to be rebuilt with robotic stone-cutters and 3D printing.

A weekly 1-minute video series uncovering how the world's most iconic structures were built — from ancient wonders to modern skyscrapers.