10 Epic Construction Projects That Took Centuries to Complete (2 of 6)

2. Cologne Cathedral (Cologne, Germany)—632 Years

Incredibly, the Cologne Cathedral broke ground in 1248, even predating the founding of the Aztec Empire on the other side of the world by nearly 200 years! Originally planned to rival the grand churches of France, construction ceased abruptly in 1473, leaving a partially constructed skeleton to languish for 300 years. But a wave of German nationalism in the 19th century revived the project, and by 1880 it was complete. For a brief time it held the title of the tallest building in the world.

3. Milan Cathedral (Milan, Italy)—Nearly 600 Years

When the Milan Duomo started being built in 1386, it was an incredible logistical undertaking, to say the least. Its famous white Candoglia marble spires—over 130 total—had to be shipped in using a complex network of canals and barges. Construction was repeatedly disrupted by changes in government control, including by Napoleon’s French Empire and later the Spanish. The last portal was put in place in 1965, officially marking the end of six centuries of construction, although to this day artisans continue to add new things onto it.