The CN Tower at 553.33 meters (1,815 ft., 5 inches) was once the tallest building, tower, and freestanding structure, but as of 2010 retains the title of world's tallest tower. Construction on the CN Tower began on February 6, 1973 and wrapped up about 40 months later in June 1976. On a clear day, visitors to the CN Tower's observation deck can see over 160 kilometers (100 miles) -- that's all the way to Niagara Falls and across Lake Ontario to New York State. Six glass-faced elevators travel at 22 km/hour (15 miles/hour) to reach the observation deck in 58 seconds. The 360 Restaurant makes a complete rotation every 72 minutes giving diners a changing view of Toronto more than 1,000 feet below.