The fifth-tallest building in the world, the Lotte World Tower, has opened in Seoul, South Korea. The event was celebrated in a ceremony with a fireworks display that lit up the building and the sky. The 123-story glass and steel structure is South Korea’s tallest building. It rises 555 meters above the Seoul skyline. The tower features the world’s highest floor made of glass. From this observation area, visitors can look straight down to the busy traffic about one-half kilometer below. The building also has the highest swimming pool in the world, as well as the world’s fastest elevator. The elevator can reportedly take passengers to the top of the building in just one minute.