The CN Tower, located in downtown Toronto, Ontario, Canada, is a communications and observation tower standing 553.3 metres (1,815 ft) tall. It surpassed the height of the Ostankino Tower while still under construction in 1975, becoming the tallest free-standing structure on land in the world for the next 31 years. On September 12, 2007 the CN Tower was surpassed in height by Burj Khalifa (formerly known as Burj Dubai). It remains the tallest free-standing structure in the Western Hemisphere, the signature icon of Toronto's skyline, and a symbol of Canada, attracting more than two million international visitors annually.