Yes, multiple historical and modern "secret" underground cities and extensive tunnel networks exist worldwide, often built for protection, mining, or military purposes. Notable examples include the ancient 85-meter deep Derinkuyu in Turkey, the 35-acre Cold War-era Burlington Bunker in the UK, and hidden, abandoned tunnels beneath cities like Seattle and London.
Some cities are so top-secret they can't even be found on a map. Others are padlocked, hidden in the forest, or buried deep underground. From Poland's 800-year-old Wieliczka Salt Mines to America's WWII mystery towns, SPYSCAPE explores some of the world's most intriguing secret cities.
Using underground space is not a new idea. From ancient catacombs to vast metro systems, cities have long looked below the surface to meet practical needs. A leading example of a functional underground city is Montreal's “RESO”, a 32-kilometer network connecting shopping malls, metro stations, offices, and residences.
Derinkuyu, in Cappadocia, is an ancient underground city dating back to the 8th century BC. It spans 18 levels and could house 20,000 people. The city features ventilation shafts, wells, kitchens, schoolrooms, etc.
Machu Picchu is a pre-Columbian Inca site situated on a mountain ridge above the Urubamba Valley in Peru. Often referred to as the "Lost City of the Incas", it is perhaps the most familiar icon of the Inca World. Machu Picchu was built around 1450, at the height of the Inca Empire.
Underground Cities in the USA You Can Actually Visit
Is Kokomondo real?
Kokomondo, believed to have been initially constructed by the Miami Indians, skilled Iron Age architects, dates back to around the 12th to 7th century BC. Over the centuries, the city was expanded and used by various civilizations, including the Fosters, who relied on it as a refuge from invasions and conflicts.
Much of the city is expected to be completed by 2030, as it is one of the focal points of Saudi Vision 2030. Some experts have expressed skepticism about the ambitions of the megaproject.
Turkey's remarkable Derinkuyu underground city lies deep beneath the surface. The city stretches to an enormous depth of approximately 85 meters (280 ft). This massive structure could shelter up to 20,000 people along with their livestock and supplies.
The Agenda 2030 Smart Cities List is a collection of cities around the world that are working towards becoming smarter and more sustainable by using technology and innovation to meet the United Nations' Sustainable Development Goals (SDGs).
The city had more than 50 ventilation shafts and natural light sources to ensure oxygen at a depth of 55 metres, which could be covered from below with huge millstones. It also had a system of water wells.
One appeal is the energy efficiency and environmental friendliness of underground dwellings. However, underground living does have certain disadvantages, such as the potential for flooding, which in some cases may require special pumping systems to be installed.
This US Metropolis Was Built Atop an Abandoned City That You Can Still Tour Today. A trip to Seattle, Washington, might take you past several interesting, above-ground attractions, like the Space Needle, Pike Place Market, and the Seattle Great Wheel.
The Boring Co.'s existing tunnel in Las Vegas. The Boring Co., founded by Elon Musk, has begun work on an underground tunnel in Nashville. Boring's “Music City Loop” would function like a rideshare.
Because of the immense pressure exerted by 30 feet of rock, sand, and silt, plus 50 feet of water, such tunnels were in danger of collapsing. To counteract this force, tunnels underwater were pumped full of pressurized air, which pressed out against the walls of the tunnel and kept it in place.
The Cappadocia region of Turkey is abundant in underground settlements and cliffside dwellings. The largest of these was Elengubu, also known today as Derinkuyu, which may have been home to up to 20,000 people.
The 55m deep air duct was also used as a well. Not every floor was given water wells up to the surface so as to shield the dwellers from poisoning during raids. Derinkuyu contains a minimum of 16,000 air-conditioning ducts that provide fresh air deep within the underground city.
Cappadocia contains several historical underground cities carved out of unusual geological formations formed via the eruptions of ancient volcanoes. The cities were initially inhabited by the Hittites, then later by early Christians as hiding places.
Upon further investigation—and some serious excavation work—the area in question was identified as Derinkuyu, an underground city in Turkey that's large enough to house up to 20,000 people.
Under Saudi Arabia's new Law of Real Estate Ownership and Investment by Non-Saudis, effective since January 2026, international buyers can purchase apartments, villas, and serviced residences in NEOM with complete ownership rights rather than just leasing arrangements.
It appears that Neom—Saudi Arabia's hugely expensive, architecturally bizarre urban development project—is floundering and close to collapse. A new report from the Financial Times cites high-level sources within the project to paint a picture of dysfunction and failure at the heart of the quixotic effort.
While NEOM is still under development, some parts are open to tourists. Specifically, the Sindalah island, a luxury resort, opened to visitors in October 2024.
In 1923, the Christian inhabitants of the region were expelled from Turkey and moved to Greece in the population exchange between Greece and Turkey, whereupon the tunnels were abandoned.
Approximately 30,000 years ago, the Paleo-Indians, the ancestors of Native Americans, followed herds of animals from Siberia across Beringia, a land bridge connecting Asia and North America, into Alaska. By 8,000 B.C.E., these peoples had spread across North and South America.
