20 Bridges and Tunnels That Took Decades to Build
Some of humanity’s most impressive infrastructure projects weren’t built overnight. While modern construction techniques can erect skyscrapers in record time, certain bridges and tunnels have demanded extraordinary patience, perseverance, and multi-generational commitment.
These projects confronted unprecedented engineering challenges, financial obstacles, political complications, and sometimes all three simultaneously. Here is a list of 20 remarkable bridges and tunnels whose construction stretched across decades, often outlasting their original planners, workers, and sometimes even the governments that initiated them.
The Brooklyn Bridge
This iconic suspension bridge connecting Manhattan and Brooklyn took years to complete, from its inception to its grand opening. Chief engineer John Roebling died before construction began, with his son Washington taking over—only to suffer debilitating decompression sickness while working in the caissons.
Washington’s wife Emily then became the de facto chief engineer, relaying instructions from her bedridden husband. The bridge’s massive stone towers and pioneering use of steel cables established new standards in bridge construction that endure to this day.
The Channel Tunnel
The “Chunnel” connecting England and France was first proposed long before construction began. However, the full project timeline spans nearly two centuries, from the initial concept to completion.
Engineers had to overcome enormous technical challenges, including coordinating two tunnel-boring teams starting from opposite shores and meeting precisely in the middle beneath the English Channel. This undersea passage remains one of the longest tunnel systems in the world.
Like Go2Tutors’s content? Follow us on MSN.
The Gotthard Base Tunnel
Switzerland spent years constructing this rail tunnel through the Alps, finally opening it to the public. The project required removing massive amounts of rock and deploying enormous tunnel-boring machines working simultaneously from multiple access points.
Engineers had to contend with varying and sometimes unexpected rock formations, extreme pressure, and temperatures reaching uncomfortable levels inside the mountain. This engineering marvel significantly reduced travel time between Zurich and Milan while shifting freight traffic from polluting trucks to more efficient rail transport.
Seikan Tunnel
This undersea rail tunnel connecting Japan’s main island of Honshu with Hokkaido took an astonishing amount of time to complete. Workers faced extraordinarily difficult conditions, including working under the Tsugaru Strait, where water pressure and unexpected soft rock formations created constant dangers.
The project claimed multiple lives during construction, with teams having to pump out enormous amounts of water in some sections. At its total length, it remained the world’s longest tunnel until another engineering feat surpassed it.
The Great Belt Fixed Link
Denmark’s massive infrastructure project connecting Zealand and Funen islands took a significant amount of time to build, though planning began decades earlier. The system includes both a suspension bridge and a tunnel, with the East Bridge featuring one of the longest main spans in the world at the time.
Engineers had to contend with the Baltic Sea’s notoriously unpredictable weather and strong currents, while the project’s immense cost required creative financing that initially made it one of the most expensive toll crossings ever built.
Like Go2Tutors’s content? Follow us on MSN.
The Three Gorges Dam Bridge
This lesser-known component of China’s massive Three Gorges Dam project took years to complete. The bridge spans the Yangtze River, allowing transportation across the enormous reservoir created by the dam.
Engineers faced the unique challenge of designing a structure that could accommodate the dramatic fluctuation in water levels between the dry and flood seasons. The project’s complex integration with the larger dam construction timeline required precise coordination of thousands of workers.
The Delaware Aqueduct Bypass Tunnel
The ongoing repair of the world’s longest tunnel, New York City’s Delaware Aqueduct, involves creating a bypass tunnel around a leaking section. This timeline doesn’t include the decades spent identifying and measuring the leaks before intervention was possible.
The work is particularly challenging because the aqueduct can’t be shut down for more than a few months without threatening New York City’s water supply, necessitating elaborate planning and precision engineering.
The Øresund Bridge
Connecting Denmark and Sweden, this combined railway and motorway link took a relatively short time to build, but its planning phase stretched back to the previous century, making the full project timeline much longer.
The engineering solution is particularly impressive, transitioning from a tunnel to an artificial island and then to a bridge. This complex design was necessary to avoid interfering with flight paths from Copenhagen Airport while still allowing shipping traffic to pass unimpeded.
Like Go2Tutors’s content? Follow us on MSN.
The Marmaray Tunnel
This underwater rail tunnel beneath the Bosporus Strait in Istanbul connects Europe and Asia. While physical construction took less than a decade, archaeological discoveries during excavation repeatedly delayed progress.
The most significant finds included the remains of a Byzantine harbor with shipwrecks, pushing the total project timeline to nearly two decades when counting initial planning. Engineers had to contend with both seismic concerns in this earthquake-prone region and the preservation of archaeological treasures simultaneously.
The Confederation Bridge
Connecting Prince Edward Island to mainland Canada, this long bridge took years to construct, but the full project timeline spans over three decades from initial studies to completion.
Engineers developed innovative construction techniques to contend with the Northumberland Strait’s harsh winter conditions, including thick ice and freezing temperatures. The bridge was designed to withstand impacts from massive ice floes pushing against its piers with tremendous force during seasonal ice breakups.
The Eisenhower Tunnel
Burrowing through the Continental Divide in Colorado, this highway tunnel took years to complete both bores. Workers faced extreme altitude challenges, including reduced oxygen levels and harsh winter conditions.
The tunnel had to be perfectly straight despite passing through varying rock formations, requiring precise calculations to ensure the two teams drilling from opposite sides would meet exactly in the middle. The resulting passage significantly improved travel between Denver and western Colorado ski areas.
Like Go2Tutors’s content? Follow us on MSN.
The Holland Tunnel
This groundbreaking underwater vehicular tunnel connecting New York and New Jersey took several years to build, but its planning began long before, making the full project span over two decades.
Chief engineer Clifford Holland solved the previously insurmountable problem of ventilating an underwater tunnel to remove deadly carbon monoxide from vehicle exhaust. The massive ventilation system he designed represented a revolutionary advance that made all subsequent vehicular tunnels possible.
The Vasco da Gama Bridge
This impressive crossing of Portugal’s Tagus River took a few years to construct, but planning and design work began decades earlier. Engineers had to account for the possibility of major earthquakes in the region, designing the bridge to withstand seismic events on a massive scale.
The project’s significant environmental impact studies and mitigation measures, including extensive monitoring of bird populations and water quality, stretched the overall timeline to nearly fifteen years.
The Thames Tunnel
The world’s first tunnel constructed under a navigable river took an astonishing number of years to complete using rudimentary Victorian-era technology. Engineer Marc Brunel invented the tunnel shield, a revolutionary device that protected workers as they excavated through soft river clay.
Floods, financial difficulties, and worker fatalities from toxic gases repeatedly halted the project. Now part of London’s railway system, this pioneering tunnel proved that underwater passages were possible, fundamentally changing urban transportation planning worldwide.
Like Go2Tutors’s content? Follow us on MSN.
Defying Gravity, Earth, and Time
These monumental projects remind us that some human achievements simply can’t be rushed. Each represents not just an engineering triumph, but a testament to sustained vision and commitment across changing political landscapes, economic conditions, and sometimes even engineering paradigms.
What separates these lengthy projects from mere delayed construction is their confrontation with genuinely unprecedented challenges—boring through mountain ranges, spanning vast bodies of water, or connecting nations previously divided by geography. These aren’t just structures; they’re physical manifestations of humanity’s determination to overcome natural barriers that once seemed insurmountable, no matter how many decades the effort might require.
More from Go2Tutors!
- 20 Historical Artifacts That Scientists Can’t Explain
- 15 Unforgettable Candy Bars From The 60s and 70’s That Disappeared Too Soon
- 20 Countries That No Longer Exist and What Happened to Them
- 20 Forgotten Fast Food Items From the 80’s That Need to Come Back
- Famous Battles: How Much Do You Really Know About U.S. History?
Like Go2Tutors’s content? Follow us on MSN.
