CN Tower

The CN Tower is quite a flabbergasting architectural achievement.

The CN Tower is a very tall structure built for media reception and communications, and it houses restaurants – one of which revolves, a theatre and a shop, and also features a number of observation decks.
Erected in Canada’s Ontario, in North America, the CN Tower was built in the middle of a disused train shunting yard, in the Railway Lands of Toronto, at a cost that totalled $63 million Canadian Dollars, and it has become a popular tourist attraction.
The ‘CN Tower’ is also known as the ‘Canadian National Tower’, ‘Canada’s National Tower’ and ‘Tour CN’, the latter in French; and ‘CN’ stands for ‘Canadian National’, the company who initially owned the tower.
The CN Tower has a central hexagonal column that has three large supports at the base, with an antenna spire at the top, and totals 553.33 metres (1,815.4 feet) in height, and has 147 floors.
The concept of the CN Tower was first proposed in 1968 by the Canadian National railway, who were the original owners of the tower and had the structure built, although it was not until early 1973 that construction commenced.

When officially opened on 1 October, 1976, the CN Tower was the tallest tower and the tallest freestanding structure in the world; and it held these positions for more than three decades, while in 2014, it ranked third and sixth respectively.
The total concrete volume used to construct the CN Tower was around 40,500 cubic metres (52,972 cubic yards), and the concrete was all made at the construction site.
Before the use of LED lights, that were installed in 2007 and are controlled in Ontario’s Burlington, the CN Tower used the original incandescent lights until around 1997, and discontinued the use of them due to expensive running and repair costs.
Ice can form on the CN Tower, which can prove hazardous in winds, as the ice can fall away from the tower and smash glass and damage objects, including cars.
The CN Tower attracts lightning due to its height, and in one year, it is hit by lightning around 75 times; and to protect against this, pieces of copper run from the top of the tower to the base and are used to direct the electrical energy into the ground.

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