When people talk about the biggest man-made structures, they focus on above-the-ground constructions forgetting amazing underground structures do exist. Erecting such structures is a momentous task for builders and engineers as they have to battle hydrostatic pressure and the weight of the soil above. These six largest man-made underground structures in the world are a testament of what humans can accomplish even against the greatest odds.
Deepest Basement – Sydney Opera House
The Sydney Opera House isn’t just an iconic landmark in the sprawling city, but an architectural marvel as well. Underneath the building is a 120-feet deep parking garage that also holds the record of the deepest basement. Initially, the builders had created an underground square but ran into legal troubles around fire escapes. They settled for a double helix making it as fascinating at the building that rests on top of it.
Longest Underground Tunnel – Gotthard Base Tunnel
The Swiss Alps is one of the fascinating geographic formations in Europe. Because of its high elevation, people have had to go around or right over them to get to the other side. However, the construction of the 35-mile Gotthard Base Tunnel from Erstfeld to Bodio, in Switzerland made the journey shorter. The tunnel goes through the Swiss Alps, and provides a flat route through the mountains. It was commissioned in 1992, but the public started using it in 2016.
Deepest Skyscraper Foundation – Salesforce Tower
Since 1836 six severe earthquakes measuring 6.75 or higher on the Richter have struck the SF Bay area. Because of the risk of tremors and quakes, skyscrapers need to have solid foundations. The 1,070-foot-tall Salesforce Tower has a foundation that’s 310 feet below grade, nearly a third of the building’s height. The builders set new seismic safety benchmarks, ensuring the tower won’t topple. Its base comprises a 14-foot thick concrete slab covering an area about an acre wide.
Largest Underground City – Derinkuyu, Cappadocia, Turkey
Going 18 stories deep, the Derinkuyu is an underground architectural marvel. The city lies beneath Capadocia. It’s vast network of tunnels looks to have been completed over a 1,000 years ago.However, it was abandoned around the start of the 20th century. It remained unexplored until 1963, when a local stumbled on its entrance in his basement. Today, the city has become a tourist attraction and a reminder of ancient architectural exploits.
Deepest Underground Research Facility – Jinping Underground Lab
Lying 7,900 feet below the ground, the Jinping Underground Laboratory provides scientists a safe haven to carry out sensitive experiments. Cosmic radiation and other factors can affect the tests and the outcome. But at this level, the influence of external factors is reduced drastically. Scientists go down there to try out new concepts and research of dark matter as well as neutrino physics.
Deepest Subway Station – Arsenala Station, Kyiv, Ukraine
Typical NYC city dwellers visit the subway stations when they want to travel around the metropolis, with the deepest being 150 feet underground. However, this pales in comparison to the depth of the Arsenala Station. At 346 deep feet, this Ukrainian underground station lies deep underground. The reason this station goes deep down is because it’s on a tall hill. However, the next stop is at ground level. To overcome the mechanical problems that might arise from travelling the hill regularly, engineers decided the subway station should be built on the hill.
Underground man-made structures bring a new perspective to the world of construction. From the deepest foundations to the deepest labs, these structures are a reminder of what humans can do when they set their mind to conquer new challenges.