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CN Tower

CN Tower

The world's tallest free-standing structure soars 1,815-feet above the sidewalks of Toronto, three times the height of its better-known cousin, the Seattle Space Needle. The CN Tower, as heavy as 23,214 large elephants, was erected at an amazing rate of 18-feet per day. During construction, concrete flowed from the bottom of the tower as it ascended, while aircraft-type bombsights kept the tower plumb as it went up. Today the tower is off by a mere 1.1-inch. Designed with the aid of a wind tunnel, the CN Tower can withstand 260-mph gusts.

The SkyPod, a seven-story structure, 1,100-feet high, was built around the base of the tower and jacked into place as one unit. A pair of 10-ton counterweights is attached to the mast to keep the tower from swaying too much. A Sikorsky helicopter hoisted the crowning antenna, for which the tower was originally erected. Radio signals are broadcast from the base of the antenna, while television signals are sent from the top. Presently, 16 of Toronto's media signals are transmitted from the tower.

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