Guangzhou, which seems to be expanding at breakneck pace, has found a new area to grow: underground.

Panyu Wanbo Underground City, which will be a total of 1.5 square kilometers in size and cost 28 billion RMB to build, will open in 2015, Guangzhou Daily reports.

The finished complex will have both an underground section (of four stories) and an overground section and will include shops, offices for rent and government offices. It will be located at Wanbo Subway Station which is on line 7.

It will take two days to walk the whole thing when it opens.

Despite the need for more space, Dongguan’s notorious ghost mall and the number of uninhabited towns in China call into question the affordability and necessity of such projects.

A Bloomberg article last year acknowledged that China needs to switch from investment-driven growth to consumption-driven growth, but China’s challenges are still formidable.