Sky Tower in downtown Auckland
Auckland picture - Sky Tower is the tallest structure in the Southern Hemisphere. There is an observation deck and two restaurants at the top. For the adventurous, there is Vertigo Climb, where you scale a ladder inside of the tower and step out onto a lookout deck near the very top of the tower (beware it's very windy). For the more adventurous, you can jump off the side of the tower and fall (while attached to a wire) down to a landing deck below.