Tribune Tower's Secret Wall: 149 Fragments of the World's History

When the Chicago Tribune announced a 1922 design competition for its new headquarters, it called for "the most beautiful and distinctive office building in the world." The Gothic tower that won, completed in 1925, is remarkable for more than its architecture: embedded in its exterior base are 149 stones and fragments collected from historically significant structures around the world. The collection began as a stunt by Tribune foreign correspondents and grew into one of the most eclectic assemblages of architectural material anywhere. Pieces include stone from the Great Wall of China, the Parthenon, the Berlin Wall, the Alamo, Westminster Abbey, the Taj Mahal, and the Great Pyramid at Giza; a moon rock was once displayed there too, on loan, in a window. Each fragment is labeled with its source. Some were donated by governments and institutions; others were obtained by Tribune correspondents who chipped pieces off historic monuments — a practice that would be considered vandalism today. One correspondent reportedly pried a piece from the ruins of Pompeii. The collection can be examined up close on a slow walk around the building's base on Michigan Avenue. Most tourists walk past it without knowing it's there.