@wtc_tribute: In skyscraper construction, "topping out" is the ceremonial placement of the final piece of structural steel. For the original North Tower of the World Trade Center (1 WTC), this historic milestone occurred on December 23, 1970. When that final steel beam was hoisted into place, the North Tower officially reached its roof height of 1,368 feet (417 meters). In that exact moment, it became the tallest building in the world, finally dethroning the Empire State Building, which had held the record for nearly 40 years. Clips based on aluminium oxyde youtube channel #WTC #TwinTowers #WorldTradeCenter #HistoryTok #EngineeringMarvel