The Golden Gate Bridge stands as one of the most recognized structures on earth. Connecting San Francisco to Marin County across a notoriously treacherous strait, it draws comparisons to the Empire State Building and the Statue of Liberty as a symbol of American ambition. In 1994, the American Society of Civil Engineers officially named it one of the seven wonders of the United States. But before it became an icon, it was a construction site — four years of steel, wire, cement, and dangerous labor carried out above cold, churning water.
Ground broke on the project in 1933. Chief Engineer Joseph Strauss led the effort alongside two key engineering consultants: Charles Ellis and Leon Moisseiff. Together, they determined that a suspension bridge was the right design for the Golden Gate. The location presented serious challenges — strong tidal currents, high winds, frequent storms, and an active earthquake zone all had to be factored into every decision. The finished bridge stretches 1.7 miles and measures 90 feet wide.
Anchorages are one of the most critical elements of a suspension bridge. Built from massive blocks of thick concrete, they are buried into the ground at each shore and grip the ends of the main cables, keeping the entire structure from pulling apart. The sheer weight and tension the anchorages must hold is enormous — they are essentially the foundation that the whole bridge hangs from.
The bridge’s two towers were fabricated from steel and rose hundreds of feet above the water during construction. Workers assembled them section by section, with riveters working in cages and on open platforms high above the bay. The south tower stands directly above Fort Point, a Civil War-era fort that was preserved intact beneath the structure — an engineering decision that required building a curved section of roadway to arch over it.
As the towers climbed skyward, the construction site became a spectacle for the entire region. Photographs from the early 1930s show the bridge in its skeletal stages, with towers rising above the waterline and temporary trestles connecting workers to the base of each structure. The project employed thousands of men during the Great Depression, making it not just an engineering feat but a vital source of work for the region.
By 1934, the Marin Tower was climbing steadily. Photos from that year show the tower at 520 feet, still short of its final height, with the surrounding landscape of Marin County visible in the background. Workers on the saddle at the top — 746 feet above the water — appear almost impossibly small against the scale of the structure. There were no harnesses of the kind modern workers rely on. Falls were a constant risk, and the job demanded nerve as much as skill.
Joseph Strauss and his team insisted on safety nets beneath the construction area — a measure that was unusual for the era. The nets saved the lives of 19 workers who fell during the project. Those men became known informally as the “Halfway to Hell Club.” Despite the nets, eleven workers died during construction, most in a single accident in February 1937 when a scaffold fell and broke through the net.
Once the towers were complete, workers began the cable-spinning process. Catwalks — long, narrow walkways strung between the towers — gave workers access to spin thousands of individual wire strands into the main cables. Each of the two main cables is made up of 27,572 individual wires. The cables are flexible by design, allowing the bridge to expand and contract with temperature changes and to swing in high winds without snapping.
By 1935, cable spinning was well underway. Workers balanced on the catwalks hundreds of feet above the water, guiding wire reels back and forth between the anchorages and the towers. The work was physically demanding and exposed workers to the full force of Bay Area weather — cold, wet, and windy conditions were the norm. Photos from this period show men moving along the catwalks with a matter-of-fact confidence that belies the danger beneath their feet.
The scale of the construction drew prominent visitors, including Labor Secretary Frances Perkins, who toured the site during construction. The project was also closely watched by the public — photographs circulated widely in newspapers, and locals tracked its progress with pride. The sight of the two towers connected by their growing web of cable became one of the defining images of 1930s San Francisco.
The cable-spinning stage required precision. Workers bundled the individual wire strands into larger groups, then compressed those groups into the final cables using hydraulic equipment. The completed main cables measure 36.5 inches in diameter. If all the wire in both cables were laid end to end, it would circle the earth more than three times.
With the main cables in place, the next phase involved hanging the vertical suspender ropes from the cables and attaching the steel roadbed sections below. This was the stage where the bridge began to look like a bridge. Sections of the roadway were lowered into position and bolted together, working outward from each tower toward the center of the span and toward each shoreline simultaneously.
Even as construction continued overhead, the strait remained an active waterway. US Navy ships passed beneath the growing structure in 1936, offering a striking contrast between military power and civil engineering. Fishermen at nearby Baker Beach watched from the shoreline as the roadbed sections were set into position, often obscured by the thick San Francisco fog that routinely rolled in off the Pacific.
Engineers surveyed the structure continuously throughout 1936, checking alignment and load distribution as each new section was added. Every beam had to be placed with precision — errors in alignment at this stage could affect the structural integrity of the entire span. The photographs from this period capture the methodical, grinding nature of the work: men with instruments, workers on platforms, steel sections swinging into position.
By late 1936 and into 1937, the roadbed was nearing completion. Workers attached steel beams and finished the surface of what would become a six-lane highway suspended above the water. The final wire strands were added to the main cables, a milestone captured in photographs showing two workmen completing the last additions to the enormous cable structure.
The bridge opened on May 27, 1937 — first to pedestrians, then to vehicles the following day. On opening day alone, 1,800 cars and 2,100 pedestrians crossed in the first hour. By midnight, an estimated 25,000 vehicles and 19,350 pedestrians had paid their tolls. The rate was fifty cents per car and five cents per pedestrian. By the end of its first full fiscal year, 3,326,521 vehicles had made the crossing. By the end of 1970, that annual figure had climbed to 33 million.
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