The leaning tower, the world's tallest inclined structure, used to retract the roof stood half finished until 1987 when the roof was finally completed.   It took another 2 years before it became retractable and due to problems with opening and closing the roof, it had been permanently closed for several seasons.   The retractable dome was silver on top and orange on the bottom with 26 white cones that linked the roof to the tower.   It took 25 minutes to hoist the roof up or down.