The world's "craziest city" is like nothing else on this planet, where trains run through apartment buildings and boats have their own skyscrapers.

Thanks to its dramatic geography and huge population of 32million, this sprawling metropolis in China has turned into a crazy maze where maps are basically useless. Ground level buildings suddenly turn into 22-storey high skyscrapers as you walk to the other side of the roof terrace, while its deepest tube station takes up to 2 hours and 45 minutes to descend. Nestled between steep mountains and deep valleys at the confluence of the Yangtze and Jialing Rivers, Chongqing has rightly earned its reputation as the "world's craziest city".