I Left My Heart in… Steel and Suspension

Hanging gracefully at the entrance to San Francisco Bay, the Golden Gate Bridge is more than a postcard icon. Completed in 1937, it was, at the time, the longest and tallest suspension bridge in the world, and a bold engineering statement built against wind, water, fog and financial uncertainty.

Designed by chief engineer Joseph Strauss, with key contributions from structural engineer Charles Ellis and architect Irving Morrow, the bridge spans 2,737 metres, with a main span of 1,280 metres. Its Art Deco styling, distinctive orange colour and elegant proportions conceal an immense feat of technical problem-solving.

Engineering the Impossible Crossing

Before construction, the Golden Gate Strait was considered nearly unbridgeable. Strong tidal currents, depths exceeding 100 metres, frequent fog and high winds created extreme working conditions.

To anchor the southern tower, crews excavated down to bedrock below open ocean, working from a sealed fender while waves and tides battered the site. The northern tower was founded on solid rock, but access and logistics remained a challenge.

Adding to the complexity, underwater air tanks had not yet been invented. Divers working on the foundations relied on surface-supplied air fed through hoses, wearing heavy canvas suits and copper helmets. Visibility was low, currents were unpredictable and decompression risks were poorly understood by modern standards. Every descent required precise coordination between surface crews and divers operating largely by feel.

The two steel towers rise 227 metres above the water and were assembled using climbing derricks, essentially early self-advancing cranes, allowing construction to progress efficiently without traditional scaffolding.

 

Spinning Steel in Mid-Air

The bridge’s most intricate work came with the main cables. Each cable is made up of 27,572 individual steel wires, spun into place one strand at a time using a moving cable-spinning wheel. In total, more than 129,000 kilometres of wire were used - enough to wrap around the Earth three times.

Once compacted and bound, the cables were strong enough to support the 887,000-tonne structure and the dynamic loads of traffic, wind and seismic activity. The deck itself was designed to flex, not fight, the elements.

Safety That Changed Construction Forever

The Golden Gate Bridge also marked a turning point in construction safety. Strauss insisted on the use of a large safety net suspended beneath the deck, a controversial decision at the time.

The net saved the lives of 19 workers, who became known as the “Halfway to Hell Club”. While 11 fatalities still occurred, the project dramatically improved safety standards for large-scale infrastructure.

A Bridge That Still Sings

Opened in May 1937, the bridge carried pedestrian traffic before vehicles, a celebration of progress at the tail end of the Great Depression. Today, it carries over 100,000 vehicles a day and continues to evolve through seismic retrofits and corrosion protection programs.

Nearly 90 years on, the bridge remains a masterclass in courage, craft and coordination, demonstrating that great infrastructure not only connects places, but also captures imaginations.