Courtesy of the Prelinger Archives, this archival 1930s footage by Bethlehem Steel captures every phase of construction of the Golden Gate Bridge. The iconic, San Francisco structure celebrated its 75th anniversary this year, as it opened May 27th, 1937. Including the approaches, the Golden Gate Bridge spans a remarkable length of 1.7 miles (8981ft or 2737m), making it the longest span in the world from its completion in 1937 until the Verrazano Narrows Bridge was built in New York in 1964. A unique aspect to the construction of the suspension bridge was the emphasis placed on safety. With the use of safety nets, hard hats and safety belts only eleven workers died during construction, which was a new safety record for the time.