Bridges do much more than carry people from one side of an obstacle to another. The best ones have opened trade routes, connected cities, accelerated the construction of railways and roads, and introduced engineering techniques that changed what could be built afterward.
From a cast-iron arch in the birthplace of the Industrial Revolution to suspension bridges spanning nearly 2 kilometers, these 10 structures stand out for their impact on transportation, society and engineering.
1. Iron Bridge – England
Completed in 1779, the Iron Bridge over England’s River Severn is widely recognized as the world’s first iron bridge. Its significance went far beyond a single crossing. It demonstrated that cast iron could be used for a major load-bearing structure at a time when the Industrial Revolution was transforming metal production.
The bridge helped establish iron as a serious construction material and became an enduring symbol of industrial-era engineering. Its construction also helped stimulate development around Ironbridge, one of Britain’s most important industrial regions.
2. Rialto Bridge – Venice, Italy
Completed in 1591, Venice’s Rialto Bridge replaced a succession of wooden crossings and became the only pedestrian link between the two sides of the Grand Canal until the 19th century.
Its single stone arch spans more than 28 meters, allowing boats to pass beneath, and thousands of timber piles support its foundations. More than a crossing, Rialto connected Venice’s political center with its commercial heart, helping people and commerce move through one of Europe’s great trading cities.
3. Menai Suspension Bridge – Wales
Thomas Telford’s Menai Suspension Bridge, opened in 1826, was a landmark in both transportation and suspension-bridge engineering. Its 579-foot main span was the world’s longest when completed, allowing the strategically important road between London and Holyhead to cross the dangerous Menai Strait.
More importantly, it demonstrated that suspension bridges could provide economical long spans for road traffic. The design influenced suspension-bridge development for decades and helped establish the form as a practical solution for major crossings.
4. Brooklyn Bridge – New York, US
When it opened in 1883, the Brooklyn Bridge was among the most ambitious infrastructure projects of the 19th century. John Roebling’s design combined a suspension system with stiffening elements and used steel cables, while enormous masonry towers supported the crossing.
Its construction also advanced techniques for working underwater in pressurized caissons. The bridge physically connected Manhattan and Brooklyn, helping knit together what would become New York City. Its engineering influence was just as significant: the project demonstrated that enormous urban suspension bridges could be built and operated successfully.
5. Forth Bridge – Scotland
Opened in 1890, Scotland’s Forth Bridge was the world’s earliest great multispan cantilever bridge. Its three enormous towers and cantilever arms produced spans of 521 meters, while about 54,000 tons of mild steel formed the structure. It was a landmark in the transition from iron to steel and demonstrated how cantilever construction could handle the heavy loads and long distances demanded by railways. It remains an active passenger and freight railway, more than 135 years after opening.
6. George Washington Bridge – New York, US
The George Washington Bridge fundamentally changed expectations for suspension bridges when it opened in 1931. Its 3,500-foot main span was nearly twice that of its largest predecessor. Chief engineer Othmar Ammann developed a lighter stiffening-truss approach that offered greater flexibility and saved nearly $10 million.
Perhaps more importantly, Ammann designed the structure with a future lower deck in mind. That foresight allowed the bridge to expand from six upper-level lanes to a massive 14-lane crossing, making it an influential example of designing infrastructure for future demand.
7. Golden Gate Bridge – San Francisco, US
The Golden Gate Bridge opened in 1937 after engineers tackled strong winds, deep water, powerful tides, and a 1.7-mile-wide strait. Its 4,200-foot main suspension span was the world’s longest at the time. More than an engineering record, the bridge transformed transportation around San Francisco Bay.
Marin County had previously depended heavily on ferries to connect with San Francisco. The project demonstrated that suspension bridges could span enormous waterways while remaining economically and structurally viable.
8. Sydney Harbor Bridge – Australia
Completed in 1932, Sydney Harbor Bridge became the centerpiece of an integrated road and rail transportation system connecting the city’s northern and southern shores. Its massive steel arch was assembled from both sides of the harbor before being joined above the water. More than 53,000 tonnes of steel and six million rivets went into the structure. The bridge wasn’t simply an engineering landmark. It helped reshape modern Sydney by creating a permanent high-capacity crossing where ferries had previously dominated movement across the harbor.
9. Akashi Kaikyo Bridge – Japan
Japan’s Akashi Kaikyo Bridge pushed suspension engineering into a new era when it opened in 1998. Its 1,991-meter central span remains the longest of any suspension bridge. Engineers had to account for severe winds, earthquakes, powerful tidal currents and deep-water foundations.
The bridge also became an important example of incorporating monitoring technology into long-span structures: sensors, GPS equipment and anemometers continuously track its behavior. Its engineering demonstrated how computer analysis, advanced materials and structural monitoring could work together on infrastructure at unprecedented scale.
10. Millau Viaduct – France
The Millau Viaduct, opened in 2004, showed how modern bridge engineering could make a highway crossing appear almost impossibly light. The cable-stayed structure stretches across France’s Tarn Valley, with its tallest mast reaching about 343 meters.
Its slender deck and multiple towers allow the highway to cross the deep valley without following the terrain below. The project demonstrated how modern materials, aerodynamic design, precision construction, and computer-assisted engineering could combine to create long, high crossings while minimizing the visual and physical footprint on the landscape.
(Rather than ranking them purely by size or age, this list looks at bridges that had an outsized influence on transportation, construction technology, or the way engineers approached large infrastructure projects.)