It's something like this. 1.Pyramids 2.Taj Mahal 3. Great Wall of China 4. Eiffel Tower 5. Colosseum 6. Parthenon ... I think the most famous U.S. buildings are the White House, Golden Gate Bridge, Statue of Liberty, and the World Trade Center, but I don't know if any are among the top 10 in the world. St. Peters, the Duomo, St. Basil, the Forbidden City, Sydney Opera House, the Pantheon, and some others are in the mix.