The CN Tower, Toronto

PD Photo: The CN Tower, the world's fourth tallest manmade structure, Toronto's most visible landmark and its most celebrated tourist destination

PD Photo: The CN Tower as seen from its base

The CN Tower, constructed in 1973-1976 for use as observation tower, telecommunications tower and a major tourist attraction, is in Downtown Toronto, Canada. The CN Tower, standing 553.33 meters (1,815.4 feet) tall, is now the fourth tallest in the list of tallest buildings and structures in the world. It attracts over two million international visitors annually.

In 1995, the CN Tower was declared one of the modern Seven Wonders of the World by the American Society of Civil Engineers. The architects of the CN Tower are John Andrews Architects and WZMH Architects (formerly known as the Webb Zerafa Menkes Housden Partnership).

Buildings and structures in the world, taller than the CN Tower are:

1. Skyscraper (all categories): Burj Khalifa, United Arab Emirates, Dubai, 828 meters (2,717 feet) tall, officially opened on 4 January 2010.

2. Guyed Mast: The KVLY-TV mast (formerly the KTHI-TV mast), Blanchard, Traill County, North Dakota, United States, 628.8 meters ( 2,063 feet) tall, completed in 1963.

3. Concrete Tower (Topped out): Canton Tower (also known as Guangzhou TV & Sightseeing Tower), near Chigang Pagoda, Haizhu District, Guangzhou, Guangdong, China, 610 meters (2,001 feet) tall, topped-out in 2009 and became operational on September 29, 2010.

4. Concrete Tower: CN Tower, Toronto, Canada, 553.3 meters/ 1,815 feet tall, opened to the public on June 26, 1976.