Vitra Slide Tower

Located near the Zaha Hadid-designed Fire Station, and accessed via the just-inaugurated Álvaro Siza Promenade, the Vitra Slide Tower is like a collision of Frank Gehry's Vitra Design Museum and Tatlin's Tower. The platform is located 17 meters (55 feet) above the ground, giving panoramic views of the Vitra campus and its buildings by Hadid, Gehry, Size, Ando, Herzog & de Meuron, and SANAA, among others. More important (and fun) is that the platform is the starting point for the 38-meter-long (124-foot) corkscrew tube slide, what Höller calls "a sculpture that you can travel inside."

Adding to the folly-like nature of the tower is the 6-meter (20-foot) diameter clockface that sits above the platform. Its slant, and the fact it has no numbers, denies an accurate reading of it as a clock. Nevertheless, every 12 hours the hands form the Vitra logo for a few brief moments. The ticking in the short film above hints at how the Vitra Slide Tower may also be considered a large solar clock, casting its shadow on the ground and adjacent buildings to mark the passing day.