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China may be one of the most advanced countries in the world with bustling cities and well developed infrastructure. But it also home to a secretive town where thousands of residents live underground.

A new aerial footage shot by a drone has now emerged, which shows a mysterious village in China Henan Province, where residents have been living underground for almost four millennia.

The settlement has about 10,000 homes and about 3,000 people living there, reported the Daily Mail, citing Chinese media reports. However, hundreds of others are said to have moved to other areas and now live in modern homes.

Called Yaodongs, the homes are mostly square or rectangular in shape and feature huge courtyards. It reportedly takes about three years to dig through the ground and build these houses and several families have been living in these sunken houses, some even going back to about six generations.

It is said that these dwellings are made under the ground level to ensure that the temperature level remains in a particular range, with very few variations. Due to this, the temperature in the winter in said to be a little over 10 degree Celsius in winter and around 20 degree Celsius in summers.

While these underground settlements may look rustic in many ways, they, in fact, boast several modern facilities, such as separate bedrooms, bathrooms, sitting rooms and functional kitchens. Some of these houses even have separate sheds for livestock, reported the Sun.

Many of these homes even have electricity and other essentials. Surprisingly, some of these dwellings are sound-proof and earthquake-resistant. And what could be considered a chef's dream come true, some of these undergrounds dwellings have well-equipped kitchens with about seven stoves. If that isn't enough, all of these stoves work at different temperatures, perfect for the chef to whip up different kinds of delicacies.

Speaking of these settlements, experts at Easy Tour China believe that the underground dwellings are "of great historical, scientific and artist value."

The Chinese media often refers to these villages as "China's most mysterious villages" and these settlements have now been listed as the nation's cultural heritage and are under conservation. These dwellings may soon be open to the public, most likely by the end of 2018, who can view the tunnels, designs and "unique architecture," according to People's Daily Online.