Hello Verruckt. The world’s tallest waterslide tests its first human sliders — appropriately enough, Jeff Henry, waterpart designer and John Schooley, ride engineer. Verruckt is an attraction at Schlitterbahn Water Park in Kansas City, Kansas. It starts with a 17-story plunge that goes into a five story uphill section (also the tallest uphill water coaster section in the world). How tall is “tallest”? At 168 foot 7 inch, the starting point is taller than Niagra Falls and should reach a maximum speed of 65 mph. Enjoy!