David Silverman/Getty Images New high-rise buildings are constructed over traditional low-level dwellings on the banks of the Yellow River on December 9, 2010 in downtown Lanzhou, the capital of China's Gansu province.

Last month China made news with the surprising announcement that a firm in the city of Changsha would attempt to build the world’s tallest skyscraper in 90 days. Now, the country is making headlines with another ambitious challenge — flattening 700 mountains in order to build a city.

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The so-called “mountain-moving project,” was actually launched in October, and not only is the scale gargantuan, but the costs are astronomical. As much as $3.5 billion will be used to blow up 700 mountains, the Guardian reports, to make room for a full-fledged city in a poor, mountainous province in northwestern China. The country’s state council approved the plan in August after years of preparation, according to China Economic Weekly magazine.

The future city, called the Lanzhou New Area, will be built on the outskirts of Lanzhou, the capital of Gansu province with a population of 3.6 million. The company behind the proposal, China Pacific Construction Group, promises to build an urban paradise, 10 square miles in size and capable of generating as much as $43 billion in GDP by 2030, China Daily reports.

The promotional video shows the new metropolis, which will cost another $11 billion to build, will be filled with high-rises, lakes, beaches and gardens.

It sounds grand — except for the fact that Lanzhou has some of the worst pollution in China, according to World Health Organization. Factories producing textiles, fertilizer and chemicals have clogged the air with smoke and particulates, while their waste has discolored the Yellow River, which runs through the province.

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Experts have raised concerns about whether the project is environmentally viable. Gansu is an arid province, surrounded by deserts and scoured by sandstorms. But China Pacific Construction Group, one of the nation’s biggest construction companies, said there is no need to worry.

“Lanzhou’s environment is already really poor, it’s all desolate mountains which are extremely short of water,” a spokesperson told the Guardian via email. “Our protective style of development will divert water to the area, achieve reforestation and make things better than before.”