We've taken our habitations to great heights with skyscrapers and mountaintop settlements. But unbeknownst to many of us, several civilizations have extended beneath the ground. Fascinating and intricate underground tunnels, burrows, caves and bunkers have been used as places of refuge from potential threats and extreme weather, as the hollows of the earth represent a safe alternative to the world above in many societies.
Here, we've chosen 6 of the most impressive underground cities in the world, to shed light (pun intended) on the stunning mastery that goes into creating a working civilisation below sea level. These extend across several continents - Asia, Europe, North Africa, Canada - and have come about for hugely varying different reasons. For some, underground cities provide relief from a difficult climate, for others protection from war or nuclear threat, and for a few the underground space has become a mere extension of a city when things have started to get too packed above ground. Some of the spaces built underground are spooky, mysterious, and altogether a bit strange. But most of all they are impressive examples of human resourcefulness.
Some of these sites are more than just a practicality. Mythical stories and tales accompany many of these underground cities, making them locations of spiritual as well as historical significance. So if the thought of a conventional overground city visit on your holidays this year bores you, then take a tour of one of these stunning underground cities, many of which are open to the public.
6 Matmata, Tunisia
In the small south Tunisian Berber town Matmata, a number of the local residents live in traditional underground ‘troglodyte’ structures. These structures are created by digging a pit in ground, around the perimeter of which caves are then dug to serve as rooms. This set up is particularly useful for sheltering the villagers from the scorching heat of the sun. Some of the homes are made up of multiple pits that are then connected by passageways.
The origins of this extraordinary place remain a mystery, although mythical stories have been passed down through the generations offering an explanation for the strange form of living. One of the most popular stories is that the village’s residents were forced to build underground shelters to protect themselves from the attack of Egyptian invaders. A myth that monsters emerged from beneath the ground to kill land usurpers spread. Impressively, the existence of the underground habitations was a little known phenomenon until 1967. The settlement was brought to general attention that year because many troglodyte homes caved in under heavy rain and residents called for help from the region’s community centre. Today most people in Matmata live off tourism, by arranging folklore exhibitions in their own homes for visitors to enjoy.
5 Sonnenberg, Switzerland
Switzerland doesn’t have any nuclear weapons nor enemies – so why does it have more underground shelter space per capita than any other country in the world? During the Cold War, a law was introduced requiring that every home built in the country since 1968 had to have a bomb shelter that could withstand a blast from a 50 megaton explosion at a distance of 700 metres. At the time, Switzerland would likely have been a key battleground for a NATO vs Warsaw Pact land war and the government wanted to guarantee its citizens’ protection. Apparently the idea for shelters came from the British using the Underground as a shelter from the blitz.
The underground shelter built at Sonnenberg was one of the most impressive - it was built in the Sonnenberg Tunnel, a 1, 550m long motorway tunnel. When it was completed it also was the largest civilian nuclear shelter in the world, designed to cater for a long term stay in the shelter if necessary: indeed, it had an operating theatre, a prison, and air filters able to meet the needs of 20, 000 people. Unfortunately, however, the realisation that the 350-tonne blast doors are in fact impossible to close has led to the dismantlement of the entire facility. Strangely, the Swiss law obligating each dwelling to possess an underground shelter still applies today. However, these days people mainly use their shelters for storing skis or wine collections.
4 Jurong Rock Caverns, Singapore
Singapore is one of the world’s biggest oil trading centres, one of its biggest bunkering ports, located on one of the most frequented shipping lanes in the world. Its position is ideal for oil storage facilities. However, demand for these facilities has boomed with growing trade and economic prosperity. Moreover, Singapore is quickly running out of industrial space. The solution? An underground village. Singapore has decided to create a new space carved into the underground rock caverns off Jurong Island to accommodate the huge demand for space. The initiative has been named the Jurong Rock Caves and represents 150 acres of underground real estate able to house 4, 200 scientists, as well as oil and gas reserves.
3 La Ville Souterraine, Québec
In Montreal, temperatures in January average at a blistering -9°C, often falling under -20°C in the winter months. It is no wonder that Montrealers have felt the need to construct an underground, heated city where you can get those everyday tasks done without fear of contracting frostbite. La Ville Souterraine (The Underground City) is located in and around Downtown Montréal and was the vision of urbanist Vincent Ponte. Construction began in 1962 and the network of tunnels and underground spaces has been developing ever since. Today, the underground city is a set of interconnected complexes: shops, business headquarters, apartment buildings, banks, offices, branches of McGill University, and hotels. These are also connected to Montreal's metro system.
2 Underground city, Beijing
Beijing's Underground City Dixia Cheng used to be an elaborate bomb shelter. It covers an area of 85 square kilometres, and is 8 to 18 metres under the surface of the earth. The network of tunnels has often been referred to as the Underground Great Wall because it was built as a site for military defense. Constructed right beneath Beijing city in 1970 in anticipation of a nuclear war with the Soviet Union, the city has been transformed into a tourist attraction, and has been open since 2000. At one time there were about 90 entrances to the complex, all of which were hidden in shops along the main streets of Qianmen.Visitors have described the complex as 'dark, damp, and genuinely eerie'.
1 Wieliczka Salt Mines, Poland
The Wieliczka Salt Mine, aka ‘The Underground Salt Cathedral of Poland’ is one of Poland’s national Historic Monuments and a UNESCO Heritage Site. The mine lies in Krakow’s metropolitan area and was built in the 13th century. The mine is 327 meters deep and over 287 kilometers long, and produced table salt from rock salt until 2007. Far from solely functioning as a place to extract salt, the mine is also a site of great beauty: An underground lake is to be found at its depth as well as dozens of statues, three chapels and a cathedral that have been carved out of the granite-like rock by generations of miners over the years. The cathedral even has chandeliers carved out of rock salt that has been worked to take on a clear, glassy appearance. The site is well worth a visit - approximately 1.2 million people visit the Wieliczka Salt Mine every year. During the Second World War, the shafts were used by occupying Germans as a location for war-related industries. Today, the mine has a radically different function, offering guided tours as well as a private rehabilitation and wellness centre.