What is the CN Tower and why is it significant?

The CN Tower is a telecommunications tower located in downtown Toronto, Canada. It was completed in 1976 and was the tallest freestanding structure in the world until 2007 when it was surpassed by the Burj Khalifa. The tower stands at a height of 553.3 meters (1,815 feet, 5 inches) and has become an iconic symbol of Toronto and Canada.

The CN Tower was built by the Canadian National Railway (CN) as a solution to the growing demand for television and radio communication in the Toronto area. The tower's construction took three years and cost CAD $63 million. It was opened to the public in 1976 and has since become a popular tourist attraction, offering views of the city and Lake Ontario from its observation decks.

The CN Tower's significance lies in its engineering and architectural feats. The tower was built using advanced engineering techniques, such as the slip-form construction method, which allowed the tower to be built quickly and efficiently. The tower's sleek and modern design also set the standard for future skyscrapers and has won numerous awards for its design and engineering.