Landmark North America
Golden Gate Bridge
The Golden Gate Bridge is a long orange bridge in San Francisco. Two tall towers hold up two giant cables. The cables hold up the road.
The Golden Gate Bridge crosses the Golden Gate, the strait where San Francisco Bay meets the Pacific Ocean. Built from 1933 to 1937, it hangs from two huge steel cables slung over towers 746 feet (227 meters) above the water, and it is painted a color called International Orange.
Led by chief engineer Joseph Strauss, the suspension bridge took 1,604 days to build, from January 5, 1933 to its opening to traffic on May 28, 1937. The District says its 4,200 ft (1,280 m) main span was the longest in the world until 1964.
Photo: Daniel L. Lu (user:dllu), CC BY-SA 4.0, via Wikimedia Commons
Discover the Golden Gate Bridge
The Golden Gate Bridge is in San Francisco, in the United States.
It crosses the water where a big bay meets the ocean. Cars, bikes and people on foot go across it. The bridge is painted orange, so it is easy to see.
The Golden Gate Bridge crosses the Golden Gate, a strait about three miles long and one mile wide where San Francisco Bay opens into the Pacific Ocean. It joins the city of San Francisco to Marin County in the north.
It is a suspension bridge: the road hangs from two giant steel cables that pass over two tall towers. With its approach roads, the bridge is 1.7 miles (2,737 meters) long. Ships sail underneath, with 220 feet (67 meters) of space above the high water.
The bridge spans the Golden Gate Strait between the San Francisco peninsula and the Marin headlands. The Golden Gate Bridge Highway and Transportation District, which runs it, gives a length of 1.7 miles (8,981 ft, 2,737 m) from abutment to abutment, a suspension span of 6,450 ft (1,966 m) and a main span of 4,200 ft (1,280 m) between the towers.
The towers rise 746 ft (227 m) above the water and 500 ft (152 m) above the roadway. The deck is 90 ft (27 m) wide and clears mean higher high water by 220 ft (67 m), the vertical clearance the War Department required in its 1930 permit. By February 28, 2019, the District counted 2,241,603,474 vehicle crossings since May 28, 1937.
- Total length
- 1.7 miles (2,737 m), with approaches
- Main span
- 4,200 ft (1,280 m)
- Towers above the water
- 746 ft (227 m)
- Built
- January 5, 1933 to May 1937
Crossing the Golden Gate
Long ago, there was no bridge here.
Many wanted a bridge, but the water was deep and windy. An engineer named Joseph Strauss led the plan. When the bridge opened, thousands of people walked across it.
The strait got its name from the explorer John C. Fremont, who called it the Golden Gate in 1846. The name has nothing to do with the bridge's color.
People dreamed of a bridge here for a long time, but the strait has strong currents, wind and fog. Chief engineer Joseph Strauss led the project, and building began on January 5, 1933. On May 27, 1937, the bridge opened for Pedestrian Day, when only people on foot could cross. The next day, President Franklin D. Roosevelt pressed a telegraph key in the White House, and cars drove over for the first time.
Fremont named the strait "Chrysopylae," or Golden Gate, in 1846, comparing it with the Golden Horn of Byzantium. Joseph B. Strauss first proposed a cantilever-suspension hybrid; in 1925 the consulting engineer Leon Moisseiff suggested a pure suspension span instead, and that idea had won out by 1929. Charles A. Ellis, Strauss's design engineer, directed thousands of stress calculations until Strauss sent him on vacation in December 1931 and then dismissed him; the District says Ellis received no credit at the time, though the record shows he deserves significant credit for the suspension design that was built.
The $35 million cost was paid by bonds, retired in 1971 entirely from tolls, with no state or federal funds apart from one approach road. Pedestrian Day on May 27, 1937 drew up to 200,000 people, according to news reports of the time. The District says the main span was the world's longest from 1937 until the Verrazano-Narrows Bridge in New York opened in 1964.
How it was built
Workers built a tower on each side of the water.
Then they spun two giant cables from thin steel wires. They hung the road from the cables. Workers wore hard hats, and a big net under the bridge caught workers who fell.
Building took 1,604 days, a little over four years. The steel for the towers was made in Pennsylvania and shipped by barge through the Panama Canal to California. For the south tower, which stands in the water, workers first built a wall called a fender and pumped the water out of it.
Next came the cables. A machine moved back and forth along each cable, laying steel wire like a loom weaving thread. Each cable holds 27,572 wires. Chief engineer Strauss made workers use hard hats and safety lines, and a rope net under the roadway caught 19 men who fell.
Ten prime contractors built the bridge, among them Pacific Bridge Company for the tower piers, McClintic-Marshall (a Bethlehem Steel subsidiary) for the towers and suspended structure, and John A. Roebling's Sons Company for the cables. Tower steel prefabricated in Pennsylvania reached California through the Panama Canal. For the south pier, crews built a fender wall and pumped out 9.41 million gallons of water; the foundation reaches 110 ft below mean low water.
Cable spinning took 6 months and 9 days, with a loom-type shuttle laying galvanized steel wire into 61 strands, 27,572 wires per cable. Strauss enforced hard hats, safety lines and a $130,000 manila rope net, which saved 19 men. Eleven men died during construction, ten of them on February 17, 1937, when a scaffold fell through the net; they are remembered on a plaque at the bridge. The District says it has no exact employment figures, so no total workforce is known.
Towers, cables and International Orange
Each tower is very tall. Its openings get smaller near the top.
Each main cable is almost one meter thick. Thin ropes hang down from them and hold the road. The orange paint is easy to see, even in fog.
The two main cables pass over the tops of the towers and are fixed at each end in huge concrete blocks called anchorages. Each cable is about 0.92 meters thick, and together they hold 80,000 miles of wire. From them hang 250 pairs of thinner ropes, 50 feet apart, which carry the road.
The architect Irving Morrow chose the color, International Orange. It blends with the hills and stands out against the sea and sky, and the District says it was chosen partly because it is easy to see in fog. The bridge is also built to move: in strong wind, the middle of the span can swing sideways.
Each main cable, 36 3/8 in (0.92 m) across and 7,650 ft long, rests on saddles atop the towers and is anchored in blocks of 60,000 tons each. Suspender ropes hang in 250 pairs, 50 ft apart; all were replaced between 1972 and 1976. Each tower holds about 600,000 rivets.
Consulting architect Irving F. Morrow gave the bridge its Art Deco form: tower portals that get smaller as they rise, vertical ribbing on the bracing, slim railings and angled lamp posts. He chose International Orange after rejecting black, gray and aluminum; the District says the U.S. Navy would have preferred black and yellow stripes. The span is designed to deflect: up to 10.8 ft downward and 27.7 ft sideways at midspan, and in the storms of 1982 it bowed about 6 to 7 ft.
- Wires in one main cable
- 27,572
- Main cable diameter
- 36 3/8 in (0.92 m)
- Wire in both cables
- 80,000 miles (129,000 km)
- Rivets in each tower
- about 600,000
The bridge today
Today, cars, buses, bikes and walkers cross the bridge every day.
Painters work on it all the time. When fog rolls in, foghorns on the bridge help ships find their way.
The bridge is never finished being painted. Salty sea air makes steel rust, so painters and ironworkers work on it all year, wherever inspections find rust. Ironworkers swap old rivets for strong steel bolts.
Fog often fills the strait, especially in summer. Since 1937, foghorns on the bridge have warned ships. In a typical year they sound about two and a half hours a day, but in the foggy season they can sound for more than five hours a day. In 1994, a group of engineers named the bridge one of the Seven Civil Engineering Wonders of the United States.
Maintenance is continuous: the District says the bridge is not painted end to end on a schedule but wherever inspections find corrosion. The original lead paint was replaced from 1968 to 1995 with a zinc silicate primer and vinyl topcoats, which became acrylic in 1990. Its current crew is 13 ironworkers and 3 pusher ironworkers, 28 painters, 5 painter laborers and a chief bridge painter.
The original concrete deck was replaced with a lighter orthotropic steel deck in 1985, widening the roadway from 60 to 62 ft, and a seismic retrofit began in 1997. The foghorns, at midspan and on the south tower pier, are switched on by bridge workers when fog limits visibility. The American Society of Civil Engineers named it one of the Seven Civil Engineering Wonders of the United States in 1994.
Amazing facts
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The bridge is not named for its color.
The bridge is named after the strait it crosses, the Golden Gate, which explorer John C. Fremont named in 1846.
Fremont named the strait Chrysopylae, or Golden Gate, in 1846, decades before the bridge; the name has nothing to do with the paint.
-
A safety net saved 19 workers who fell.
A rope net under the road caught 19 workers who fell, and every one of them was saved.
The $130,000 manila rope net, extending ten feet beyond the trusses, saved 19 men, who became known as the Halfway-to-Hell Club.
-
The bridge can move up and down!
The bridge is built to move. In the middle, the road can go up and down by as much as 16 feet (about 5 meters).
At midspan the deck is designed for up to 10.8 ft of downward and 5.8 ft of upward deflection, a range of about 16 ft, as loads and temperatures change.
-
On the first day, only walkers could cross.
On May 27, 1937, the bridge opened for Pedestrian Day, when only people on foot could cross. Cars came the next day.
Pedestrian Day, May 27, 1937, opened the whole roadway to walkers from dawn to dusk; news reports estimated up to 200,000 people took part.
Words to know
- suspension bridge
- a bridge whose road hangs from cables slung over towers
- strait
- a narrow stretch of water that joins two larger bodies of water
- main span
- the longest part of a bridge, between its two main towers
- anchorage
- a huge, heavy block at each end of a suspension bridge that holds the cables tight
- fender
- a protective wall built around a bridge pier in the water
- corrosion
- slow damage to metal, such as rust, caused by air, water and salt
Discovery challenge
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Which city is the Golden Gate Bridge in?
Which city stands at the south end of the Golden Gate Bridge?
Which city's peninsula forms the southern side of the Golden Gate Strait?
- San Francisco
- Seattle
- Miami
Show the answer
San Francisco
San Francisco! The bridge is by the ocean, in California.
The bridge joins San Francisco, in the south, to Marin County in the north.
The strait lies between the San Francisco peninsula and the Marin headlands.
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What holds the road up?
What holds up the road of the Golden Gate Bridge?
What carries the deck of a suspension bridge like the Golden Gate?
- Two giant cables
- Floating boats
- Stone arches
Show the answer
Two giant cables
Two giant cables! They go over the tall towers.
The road hangs from ropes attached to two giant steel cables that pass over the towers.
Suspender ropes in 250 pairs hang from two main cables, which rest on saddles on the towers and are fixed in anchorages.
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What is the bridge's color called?
What is the name of the bridge's color?
Which color did consulting architect Irving Morrow choose for the bridge?
- International Orange
- Golden Yellow
- Ocean Blue
Show the answer
International Orange
International Orange! It is easy to see.
It is called International Orange. It blends with the hills and is easy to see in fog.
International Orange, chosen after Morrow ruled out black, gray and aluminum.
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Why do painters work on the bridge all the time?
Why is the bridge painted all year round?
What is the main reason the District paints the bridge continuously?
- Salty air makes steel rust
- Birds eat the paint
- The color changes every year
Show the answer
Salty air makes steel rust
The salty sea air makes the steel rusty. Paint keeps it safe.
Salty air from the sea makes steel rust, so painters repaint wherever rust starts.
The paint protects the steel from the salt-laden air that corrodes it, and work follows inspections that find advancing corrosion.
-
What did the builders wear on their heads?
What safety gear did Joseph Strauss make every worker wear on their head?
Which piece of safety equipment, modified from a mining helmet, did Strauss require on the job?
- Hard hats
- Swimming caps
- Paper hats
Show the answer
Hard hats
Hard hats! They kept the builders' heads safe.
Hard hats, along with safety lines and a big net under the road.
Edward W. Bullard's hard hat, adapted from his mining helmet. The District quotes author Stephen Cassady: it was the first big job to enforce hard hats and safety lines with the threat of dismissal.
Nearby places
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Watch
City
San Francisco
San Francisco sits on the tip of a peninsula between the Pacific Ocean and San Francisco Bay in California. Spanish settlers arrived in 1776, the Gold Rush that began in 1848 turned it into a booming port, and today it is famous for the Golden Gate Bridge, its cable cars, its steep hills and its summer fog.
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Natural wonder
Yosemite National Park
Yosemite National Park lies in California's Sierra Nevada mountains. Its granite cliffs, rounded domes and tall waterfalls were shaped by rivers and then by glaciers, which turned narrow canyons into wide U-shaped valleys. It is also home to giant sequoia trees and hundreds of black bears.
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City
Los Angeles
Los Angeles is the second-biggest city in the United States, spread across a wide plain between the mountains and the Pacific Ocean. Founded in 1781 as a small farming village, it grew into a world center of movies and music. About 3.9 million people lived there in 2020.
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Natural wonder
Bryce Canyon National Park
Bryce Canyon National Park, in southern Utah, is not really a canyon. It is a row of giant bowls, called amphitheaters, carved into the edge of a high plateau and filled with colorful rock spires called hoodoos. The park says it has the largest collection of hoodoos in the world. Ice and rain shaped them from rocks first laid down in an ancient lake.
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Natural wonder
Grand Canyon
The Grand Canyon is a huge, steep-sided canyon in Arizona carved by the Colorado River. It is about 447 kilometers long and, on average, 1.6 kilometers deep, and its walls show layers of rock almost two billion years old.
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Natural wonder
Rocky Mountains
The Rocky Mountains, or Rockies, stretch about 4,800 kilometers from northern Canada to New Mexico in the United States. They include more than 100 separate ranges, and their highest peak, Mount Elbert in Colorado, is 4,399 meters tall. Glaciers carved their peaks and valleys, and famous parks such as Banff, Jasper and Yellowstone protect their lakes, hot springs and wildlife.
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Natural wonder
Yellowstone National Park
Yellowstone National Park sits on top of a giant volcano in the western United States. Heat from melted rock deep underground powers more than 10,000 hot springs, geysers, mudpots and steam vents, and the park is home to bison, wolves and two kinds of bears.
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Natural wonder
Banff National Park
Banff National Park lies in the Rocky Mountains of Alberta, in western Canada. It began in 1885 around a group of hot springs, which makes it Canada's first national park. Today it covers 6,641 square kilometers of jagged peaks, glaciers, forests and turquoise lakes such as Lake Louise and Moraine Lake, and it is home to grizzly bears, wolves, elk and many more animals.
Experiments to try
- Watch Try it What If? Lab What if a bridge were twice as long? A steel beam bridge 20 meters long sags about 14 millimeters under a 20-tonne truck. Make it twice as long and the sag does not just double: in our model it grows almost 14 times. Find out why long bridges need different designs.
- Watch What If? Lab What if metal never rusted? Rust forms when iron and steel react with oxygen and water. It slowly eats away bikes, gates and even giant bridges, so people fight it with paint, zinc and special steels. Imagine a world where metal never rusted and follow what might change.
Explore next
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Country
United States
The United States is a large country in North America made of 50 states, from icy Alaska to the warm islands of Hawaii. It has the Grand Canyon, the Mississippi River and Yellowstone, and about 342 million people live there.
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City
San Francisco
San Francisco sits on the tip of a peninsula between the Pacific Ocean and San Francisco Bay in California. Spanish settlers arrived in 1776, the Gold Rush that began in 1848 turned it into a booming port, and today it is famous for the Golden Gate Bridge, its cable cars, its steep hills and its summer fog.
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Watch
Landmark
Brooklyn Bridge
The Brooklyn Bridge crosses the East River between Brooklyn and Manhattan in New York City. Built from 1869 to 1883, it was the first bridge to use steel wire for its cables, and its main span was the longest in the world until 1890. Every day, cars, walkers and cyclists still cross it.
- Watch Try it What If? Lab What if a bridge were twice as long? A steel beam bridge 20 meters long sags about 14 millimeters under a 20-tonne truck. Make it twice as long and the sag does not just double: in our model it grows almost 14 times. Find out why long bridges need different designs.
- Watch What If? Lab What if metal never rusted? Rust forms when iron and steel react with oxygen and water. It slowly eats away bikes, gates and even giant bridges, so people fight it with paint, zinc and special steels. Imagine a world where metal never rusted and follow what might change.
-
Watch
City
Los Angeles
Los Angeles is the second-biggest city in the United States, spread across a wide plain between the mountains and the Pacific Ocean. Founded in 1781 as a small farming village, it grew into a world center of movies and music. About 3.9 million people lived there in 2020.
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Watch
Landmark
Tower Bridge
Tower Bridge crosses the River Thames in London, beside the Tower of London. Built from 1886 to 1894, it has two stone-covered towers joined by high walkways, and a road that splits in the middle and swings up like two giant seesaws to let tall ships pass. It still opens about 850 times a year.
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Landmark
Chichén Itzá
Chichén Itzá is the ruin of a great Maya city on the Yucatán Peninsula in Mexico. Its people built pyramids, a huge ball court and a round building for watching the sky. Its most famous pyramid, El Castillo, has 365 steps, as many as the days in a year.
For parents & teachers
What children will learn
- Locate San Francisco and the Golden Gate Strait on a map.
- Explain how a suspension bridge carries its road on cables and towers.
- Describe how the bridge was built and how workers were kept safe.
- Explain why steel near the sea needs constant painting.
Recommended ages: 3 to 17 · About 15 minutes
Talk about it
- Why do you think it was hard to build a bridge across this strait?
- The bridge is built to move in the wind. Why might bending be better than being completely stiff?
- Charles Ellis did important design work but got no credit at the time. Why does it matter who gets credit for teamwork?
Try at home or in class
- Make a model suspension bridge: tie string between two stacks of books, hang paper clips from it and lay a strip of card on the clips as the road.
- Twist several thin threads into one cord and compare how much weight it can hold against a single thread.
Key vocabulary: suspension bridge, strait, main span, anchorage, fender, corrosion
Where these facts come from
- Wikidata , Wikimedia Foundation (CC0 1.0)
- Design & Construction Stats , Golden Gate Bridge, Highway and Transportation District
- Construction , Golden Gate Bridge, Highway and Transportation District
- Bridge Design , Golden Gate Bridge, Highway and Transportation District
- Frequently Asked Questions , Golden Gate Bridge, Highway and Transportation District
- Key Dates in Bridge History , Golden Gate Bridge, Highway and Transportation District
- Opening Fiesta Week , Golden Gate Bridge, Highway and Transportation District
- Color & Art Deco Styling , Golden Gate Bridge, Highway and Transportation District
- Painting the Bridge , Golden Gate Bridge, Highway and Transportation District
- Foghorns & Beacons , Golden Gate Bridge, Highway and Transportation District
- What's In a Name - The Golden Gate? , Golden Gate Bridge, Highway and Transportation District
- Joseph Strauss , Golden Gate Bridge, Highway and Transportation District
- Wikimedia Commons , Wikimedia Foundation (Per file (public domain, CC0, CC BY or CC BY-SA); see each media record)
Checked, not yet human-reviewed. Last updated October 24, 2026. Spotted a mistake? Tell us.