On today’s date in 1975, high-rigger Paul Mitchell topped off the CN Tower, which was world’s tallest freestanding structure, at 553 metres, until 2010.
In 2006, the Royal Canadian Mint struck a $20 Proof silver coin to mark the 30th anniversary of the opening of the CN Tower. The coin, which weighs 31.1 grams with a 38 mm diameter, features a stylized holographic design of the tower during a lightning storm. It was the second issue in the Architectural Treasures series, following the 2006 Notre Dame Basilica of Montreal coin.
Designed by John Andrews International, the CN Tower was the world’s tallest freestanding structure and had the world’s highest public observatory until 2010, when Dubai’s Burj Khalifa officially took the honour.
The CN Tower has 147 floors from the internal staircase between the ground and the Skypod, the public observation deck near the top of the tower. Constructed by Canadian National Railroad, the tower was originally built to improve television reception. It cost $63 million to build.