Introduction
Modern engineering has pushed bridge construction to extraordinary lengths. The longest bridges on Earth stretch for dozens or even hundreds of kilometers, crossing rivers, bays, marshlands, and open water. Most of the record holders were built in the 21st century, reflecting advances in materials science, construction techniques, and economic investment.
China dominates the list, with six of the top 10 longest bridges in the world. Here are the 10 longest bridges ranked by total length.
1. Danyang-Kunshan Grand Bridge
- Length: 164.8 km (102.4 mi)
- Location: Jiangsu, China
- Type: Railway viaduct
- Opened: 2010
The Danyang-Kunshan Grand Bridge is the longest bridge in the world by a wide margin. Part of the Beijing-Shanghai High-Speed Railway, it carries trains across the Yangtze River Delta between Shanghai and Nanjing. Construction took four years and employed approximately 10,000 workers.
The bridge crosses Yangcheng Lake for 9 km, but most of its length spans low-lying rice paddies and floodplains. It was built elevated to save farmland and avoid disrupting ground-level infrastructure.
2. Changhua-Kaohsiung Viaduct
- Length: 157.3 km (97.8 mi)
- Location: Taiwan
- Type: Railway viaduct
- Opened: 2004
This viaduct carries Taiwan's High-Speed Rail along the western coastal plain of the island. It was designed as an elevated structure to minimize land acquisition in the densely populated corridor between Changhua and Kaohsiung.
The viaduct is also engineered to withstand the frequent earthquakes and typhoons that affect Taiwan, with seismic isolation bearings at key points.
3. Cangde Grand Bridge
- Length: 115.9 km (72.0 mi)
- Location: Hebei, China
- Type: Railway viaduct
- Opened: 2010
Another segment of the Beijing-Shanghai High-Speed Railway, the Cangde Grand Bridge crosses the vast flat plains of Hebei Province. Like the Danyang-Kunshan bridge, it was built elevated to preserve agricultural land.
High-speed trains cross this bridge at speeds exceeding 300 km/h, completing the journey in under 25 minutes.
4. Tianjin Grand Bridge
- Length: 113.7 km (70.6 mi)
- Location: Tianjin-Langfang, China
- Type: Railway viaduct
- Opened: 2010
The Tianjin Grand Bridge is the fourth segment of the Beijing-Shanghai corridor to make this list. It connects Beijing's outskirts through Tianjin municipality. The bridge was completed as part of China's massive high-speed rail expansion program.
The bridge's construction used a segmental approach, with precast concrete segments lifted into place by specialized gantry cranes moving along the completed sections.
5. Weinan Weihe Grand Bridge
- Length: 79.7 km (49.5 mi)
- Location: Shaanxi, China
- Type: Railway viaduct
- Opened: 2008
This bridge carries the Zhengzhou-Xi'an High-Speed Railway across the Wei River valley. It crosses the Wei River twice and runs parallel to it for much of its length, traversing the floodplain of one of China's historically most important rivers.
The Wei River valley is known as the cradle of Chinese civilization, and the bridge passes through one of the most historically significant regions in the world.
6. Hong Kong-Zhuhai-Macau Bridge
- Length: 55 km (34.2 mi)
- Location: Pearl River Delta, China
- Type: Road bridge-tunnel
- Opened: 2018
This is the longest sea-crossing bridge in the world. It connects Hong Kong, Macau, and Zhuhai across the Pearl River Delta. The structure includes a 6.7 km undersea tunnel and two artificial islands, allowing large ships to pass through the busy shipping channel.
The bridge was designed to withstand Category 16 typhoons and magnitude 8 earthquakes. It reduced the travel time between Hong Kong and Zhuhai from four hours to about 30 minutes.
7. Bang Na Expressway
The Bang Na Expressway is a six-lane elevated highway running above ground-level roads in the Bangkok metropolitan area. It was built to relieve severe traffic congestion on the route between Bangkok and its eastern suburbs.
When completed in 2000, it was the longest bridge in the world. It held that record until China's high-speed rail viaducts surpassed it a decade later.
8. Beijing Grand Bridge
- Length: 48.2 km (29.9 mi)
- Location: Beijing, China
- Type: Railway viaduct
- Opened: 2010
The Beijing Grand Bridge is yet another section of China's remarkable Beijing-Shanghai High-Speed Railway. It serves the approach into Beijing from the southeast, crossing suburban areas and river valleys.
The bridge exemplifies China's preference for elevated rail lines in populated areas, which avoids the need for level crossings and reduces land acquisition.
9. Lake Pontchartrain Causeway
- Length: 38.6 km (24.0 mi)
- Location: Louisiana, United States
- Type: Road bridge over water
- Opened: 1956 (northbound), 1969 (southbound)
The Lake Pontchartrain Causeway consists of two parallel bridges crossing Lake Pontchartrain in southern Louisiana. For decades it was considered the longest bridge over water in the world, and it remains the longest continuously over water (not counting artificial islands or tunnel sections).
At the midpoint of the bridge, you cannot see land in any direction. The causeway has survived multiple hurricanes, including Hurricane Katrina in 2005.
10. Manchac Swamp Bridge
- Length: 36.7 km (22.8 mi)
- Location: Louisiana, United States
- Type: Road bridge
- Opened: 1979
The Manchac Swamp Bridge carries Interstate 55 across the Manchac Swamp in southern Louisiana. The swamp is one of the most inhospitable wetlands in the United States, filled with cypress trees, alligators, and dense vegetation.
Building through swampland required driving thousands of concrete piles deep into the soft ground to reach stable bedrock.
Key Facts
- The Danyang-Kunshan Grand Bridge is over four times longer than the next non-Chinese bridge on the list.
- Six of the top 10 longest bridges are in China, all built since 2008.
- The Hong Kong-Zhuhai-Macau Bridge is the longest sea-crossing bridge at 55 km.
- The Lake Pontchartrain Causeway is the longest bridge continuously over water.
- China's high-speed rail network uses elevated viaducts to save farmland and avoid conflicts with ground traffic.
Fun Facts
- The Danyang-Kunshan Grand Bridge used enough concrete to build a sidewalk from Earth to Mars (at closest approach).
- At the center of the Lake Pontchartrain Causeway, you cannot see land in any direction on a clear day.
- The Hong Kong-Zhuhai-Macau Bridge includes a segment designed to let ships up to 300,000 tonnes pass beneath it.
- The Manchac Swamp through which I-55 passes is said to be haunted, according to Louisiana folklore.
Final Thoughts
The longest bridges in the world are testaments to human engineering ambition. From China's vast high-speed rail viaducts to the swamp-spanning highways of Louisiana, these structures solve geographic challenges that once seemed impossible to overcome.