The 1,797 foot high television tower is Toronto’s landmark. The Canadian National Tower received its abbreviation from Canadian National Railways, one of the main companies that banded together to have the tower erected. Construction began in 1973 and three years later the CN Tower was opened to the public. Renovations have been an ongoing project since the Tower’s inception, including the addition of a huge glass floor and a revolving restaurant. The Canadian National Tower is currently the third highest television tower on earth.