Height: 553.33 meters (1,815 feet, 5 inches), world's tallest tower. Construction began: February 6, 1973. Construction completed: June 1976. Original cost: $63 million. Earthquake standard: built to withstand an earthquake of 8.5 on the Richter scale. Wind standard: up to 418 km/h (260 mph). Lightning strikes: This tower averages 75 lightning strikes per year. Long copper strips run down the CN-Tower and are connected to grounding rods that are buried into the ground to prevent damage.