This photo was taken in Chongqing , China. One of the characteristics of buildings in Chongqing is that they are not built after the land has been cleared , but rather , the topography is left as it is to create an integrated look. At first glance, the apartment building in this photo looks like it is reflecting the top and bottom , but it is not. The blue line spreading horizontally across the building is the first floor , with the upper part above ground and the lower part underground. Of course, it is possible to enter the building from the bottom floor , but there is also an entrance on the outside , from which you can also go in and out.