Golden Gate Bridge

The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, the one-mile-wide (1.6 km) strait connecting San Francisco Bay and the Pacific Ocean. It links the city of San Francisco, California, at the northern tip of the San Francisco Peninsula, to Marin County, carrying both U.S. Route 101 and California State Route 1 across the strait. The bridge also accommodates pedestrian and bicycle traffic and is designated as part of U.S. Bicycle Route 95. Recognized by the American Society of Civil Engineers as one of the Wonders of the Modern World, the bridge is one of the most internationally recognized symbols of San Francisco and California.

Historical Background

The idea of a fixed link between San Francisco and Marin gained popularity in the late 19th century, but it was not until the early 20th century that it became feasible. Joseph Strauss served as the chief engineer for the project, with significant contributions from Leon Moisseiff, Irving Morrow, and Charles Ellis. The bridge opened to the public in 1937 and has undergone various retrofits and improvement projects since then.

Design and Construction

Described by Frommer's travel guide as "possibly the most beautiful, certainly the most photographed, bridge in the world," the Golden Gate Bridge held the titles of both the longest and the tallest suspension bridge in the world at its opening in 1937. It maintained these titles until 1964 and 1998, respectively. The main span is 4,200 feet (1,280 m) long, and the total height is 746 feet (227 m).

Before the bridge was built, the only practical short route between San Francisco and Marin County was by boat. Ferry service began as early as 1820, with a regularly scheduled service starting in the 1840s to transport water to San Francisco. In 1867, the Sausalito Land and Ferry Company began operations, and in 1920, the Golden Gate Ferry Company took over the service, merging in 1929 with the Southern Pacific Railroad's ferry system to become the largest ferry operation in the world.

Engineering Challenges

Many experts initially believed that a bridge across the 6,700-foot (2,000-meter) strait, with its strong, swirling tides and currents, deep water (372 ft / 113 m at the center), and frequent strong winds, could not be built. Despite these challenges, construction began on January 5, 1933. The project cost over $35 million (equivalent to $610 million in 2023) and was completed ahead of schedule and under budget. The construction was carried out by the McClintic-Marshall Construction Co., a subsidiary of Bethlehem Steel Corporation.

Safety Innovations

Joseph Strauss oversaw day-to-day construction and made groundbreaking contributions, including the use of movable safety netting beneath the workers, which saved many lives. Nineteen men saved by the nets formed the Half Way to Hell Club, although eleven men were killed in falls, ten of whom died on February 17, 1937, when a scaffold fell into and broke through the safety net.

Modern Enhancements

The Golden Gate Bridge has undergone several enhancements to improve its resilience and functionality. For example, the bridge has been designed to withstand winds of up to 68 mph (109 km/h). It has only been closed three times due to weather conditions. As part of the retrofitting and installation of a suicide barrier, the railings on the west side of the pedestrian walkway were replaced with thinner, more flexible slats to improve aerodynamic tolerance of high winds up to 100 mph (161 km/h).

In June 2020, reports emerged of a loud hum produced by the new railing slats when strong west winds blew. This sound, which was predicted from wind tunnel tests but not included in the environmental impact report, is being addressed. The hum comprises various Aeolian tones produced by the wind blowing across the metal slats.

Visitor Experience

The Round House Café, an Art Deco design by Alfred Finnila completed in 1938, has been a popular starting point for tours of the bridge and housed an unofficial gift shop until renovations in 2012. The bridge is accessible to pedestrians and cyclists and serves as a vital and picturesque route for locals and tourists alike.