2. Taipei 101

Ahh, Taipei 101. Tristan was almost beside himself, bouncing around like a kid at Christmas, at the thought of entering the World's Tallest Building. Some facts: it's 509 m tall, has 101 floors above ground, and contains the worl'd fastest elevator which travels at 16.83 m/s (see further down the list). Taipei 101 will remain the tallest building for a few more years, until it's eclipsed by the Burj Dubai in the UAE, which is still under construction. Tristan says: "No one has ever been in a taller building than us. Awesome!"