Long overshadowed by its more famous neighbor, the San Francisco-Oakland Bay Bridge is, in actuality, a lengthy set of bridges that spans San Francisco Bay and connects the two cities.

1. THE BRIDGE WAS CONCEIVED DURING THE GOLD RUSH.

The California Gold Rush of the mid-19th century swelled San Francisco’s population to more than 30,000 in just a few years as Americans and immigrants arrived by the thousands. But the completion of the nation’s first transcontinental railway disconnected the city from the railroad (which ultimately had its terminus in Oakland), so in 1872 a Bay Bridge Committee convened to work with the rail company to construct a bridge and connect it to the existing rail line. The project, however, never came to fruition due to financial and technological impediments.

2. A SELF-PROCLAIMED EMPEROR DEMANDED THE BRIDGE.

An eccentric British businessman named Joshua A. Norton traveled to California seeking fortune during the Gold Rush, but fell on hard times after failing to secure the rice market. He became a colorful local character and eventually dubbed himself Norton I, Emperor of the United States and Protector of Mexico, and charmed newspaper writers and other business owners with his fanciful outfits and wild decrees. His most famous, in 1872, commanded “a bridge be built from Oakland Point to Goat Island (later Yerba Buena) and thence to Telegraph Hill.” He was immortalized by Mark Twain as the King in Adventures of Huckleberry Finn, and Norton and his ideas are still celebrated and championed by a local nonprofit.

3. A TINY ISLAND WAS KEY TO BUILDING THE BRIDGE.

Once informally called Wood Island and Sea Bird Island, and officially Goat Island, Yerba Buena Island (which means “good herb” in Spanish and was also the name of the settlement that became San Francisco) lies in San Francisco Bay just below Treasure Island. In order to span the length of the bay, engineers—led by California State Highway Engineer Charles C. Purcell—needed to include the island, which sits 1.78 miles from San Francisco and was used as a base by both the U.S. Army and Navy. With their permission, a 76-foot wide, 56-foot high bore tunnel, the largest in the world, was dug through a shale hill on Yerba Buena and connected the East and West bridge sections.

4. NEW TECHNIQUES WERE DEVISED TO BUILD THE ANCHORAGE.

A February 1935 article in Popular Science detailed the incredible work done by engineers to construct the bridge over eight miles of land and the San Francisco Bay. To secure the anchorage midway between San Francisco and Yerba Buena Island, workers tugged a caisson (patented by New York engineer Daniel E. Moran) that supported 55 steel tubes filled with air to the location in the bay. They lowered it 100 feet into the thick mud and used water jets and a clamshell bucket to scoop out detritus and anchor the caisson within the bedrock 220 feet below the water’s surface.

5. THE PROJECT IS REALLY THREE BRIDGES IN ONE.

To reach Yerba Buena Island from downtown San Francisco, the bridge’s designers built a pair of suspension bridges that connected at the center anchorage. From Yerba Buena to Oakland they constructed a third bridge, composed of a cantilever bridge and viaduct. All told, the trio of bridges (and the tunnel on Yerba Buena, not counting approaches, toll plazas, and similar structures) spanned 23,000 feet, or 4.5 miles.

6. WORKERS FINISHED WELL AHEAD OF SCHEDULE.

The California Legislature created the Toll Bridge Authority in the late 1920s to begin the process of building a bridge across San Francisco Bay. Construction began on July 9, 1933 with a groundbreaking ceremony marked by a flyover, musical performances, and concurrent detonations at Yerba Buena, San Francisco, and Oakland performed by President Franklin D. Roosevelt from the White House. Just three years later, on November 12, 1936, the bridge officially opened to traffic, ahead of schedule and below budget at around $77 million. To celebrate, a five-day ceremony was held, complete with parades, a regatta, and a Navy air show.  

7. LAX SAFETY REGULATIONS LED TO NUMEROUS DEATHS.

A well-known principle at the time of the bridge’s construction was that for every $1 million spent on a high-steel project, the public could expect one worker fatality. Out of the 8300 men who worked on the bridge, 24 ultimately perished. By comparison, around 27 workers (out of 600) died constructing the Brooklyn Bridge, and 11 died building the nearby Golden Gate Bridge, though a support net saved 19 men from plummeting to their deaths.

8. THE BRIDGE WAS NEVER GIVEN AN OFFICIAL NAME.

James Rolph served as mayor of San Francisco from 1912 to 1931, earning the nickname “Sunny Jim” from his use of the song “Smiles” as his campaign theme song. He was then elected governor of California in 1931 but died in office three years later. The bridge’s builders planned to honor Rolph by naming the structure after him, but local political heavyweight Joseph R. Knowland blocked the measure, and it wasn’t until the 50th anniversary of the bridge’s opening that Rolph was unofficially honored. The bridge’s name, however, is still listed as the San Francisco-Oakland Bay Bridge.

There have been a handful of attempts to pass a measure to rename the bridge after Emperor Norton that have failed, but in 2014 the western span of the bridge was named in honor of former mayor and Assembly Speaker Willie Brown.

9. HEAVY FOG NEAR THE BRIDGE CAUSED MAJOR AIR ACCIDENTS.

In 1968 a T33 Navy training aircraft left Alameda Naval Air Station carrying two officers, but in heavy fog the small plane struck a cantilever arch 15 feet above the eastern span of the Bay Bridge roadway, burst into flames, and fell into the bay, killing both pilots and sending debris onto moving vehicles. A similar accident occurred in 1943 when a Grumman Wildcat hit a suspension cable and killed the Navy pilot.

10. THE BRIDGE CONTRIBUTED TO A MAJOR OIL SPILL.

On November 7, 2007, the Cosco Busan oil tanker hit the base of the bridge’s Delta Tower and spilled around 53,500 gallons of fuel into the bay, forcing Governor Arnold Schwarzenegger to declare a state of emergency. The spill killed thousands of birds and caused over $1 million in structural damage and $70 million in cleanup costs. The ship’s pilot, John Cota, later pled guilty to two misdemeanors and was sentenced to 10 months in federal prison.

11. THE 1989 EARTHQUAKE SHUT DOWN THE BRIDGE.

The 6.9 magnitude Loma Prieta earthquake that struck the San Francisco area during the 1989 World Series resulted in the deaths of 63 people and about $5 billion in damages. The quake, centered in the Forest of Nisene Marks State Park in the Santa Cruz Mountains, sheared the bolts holding the upper deck of the eastern span of the Bay Bridge, causing a 50-foot section to plummet to the lower level and kill one person. It took workers a month to repair, and it reopened to traffic on November 16.

12. THE EASTERN SPAN WAS COMPLETELY REPLACED.

The 1994 Northridge Earthquake in southern California caused state leaders to rethink their strategy of simply repairing the eastern span. But to replace the entire 2.2-mile section of the bridge took five years of planning and the approval of multiple state agencies just to begin work on the $6.4 billion project. Construction officially began in 2002, and nearly 8000 workers built a Skyway viaduct, self-anchored suspension bridge, S-curve, and 526-foot tower that will allow the bridge to withstand a Maximum Creditable Earthquake (MCE) of 8.5 magnitude. The new span opened to traffic in September 2013, while the three-phase demolition of the old span will take three to five years to complete.

13. VISITORS ARE NOW TREATED TO A FANCY LIGHT SHOW.

Not long after the 75th anniversary of the Bay Bridge’s 1936 opening, New York artist Leo Villareal created an illuminated installation that spanned the western portion of the bridge called “The Bay Lights.” Villareal and a team of engineers, designers, electricians, and other experts installed 25,000 LED lights along the 1.8-mile, 500-foot high span, which he controlled from his laptop with a specially developed software program. The project was privately financed with $8 million in Silicon Valley donations, and it lit the Bay every night from March 2013 to March 2015. But the project proved so popular (an impact assessment estimated it added nearly $100 million to the local economy) that an additional $4 million was raised to make the installation permanent, and it reopened on January 30, 2016 as one of the leadoff events to Super Bowl 50.