Did you know that the Burj Khalifa in Dubai, United Arab Emirates, is the tallest building in the world, standing at a staggering 828 meters tall? Another iconic structure, the Eiffel Tower in Paris, France, was originally built as a temporary exhibit for the 1889 World's Fair. In Italy, the Leaning Tower of Pisa is a popular tourist attraction due to its unintentional tilt caused by an unstable foundation. Moving over to the United States, the Empire State Building in New York City was once the world's tallest building before being surpassed by the World Trade Center. Meanwhile, the Sydney Opera House in Australia is known for its unique sail-like design and hosts over 1,500 performances annually. In China, the Great Wall is an architectural marvel that spans over 13,000 miles and was built over several centuries to protect against invasions. The Taj Mahal in India is a stunning example of Mughal architecture and was built as a mausoleum for Emperor Shah Jahan's wife. Lastly, the Colosseum in Rome, Italy, is an ancient amphitheater where gladiator contests and public spectacles took place. These buildings are not only impressive feats of architecture but also serve as important cultural landmarks around the world.