the chongquing river is the largest in asia.ocated upstream, it's developed into a major port for river transport. chongquing is a directly controlled municipality of china, along with beijing and shanghai. it used to be a part of szechwan province but given its current designation as part of an effort to develop innercities that had fallen behind coastal regions due to the effects of reform policies. recently chongquing has been further developed as a hub connecting china and europe. thanks to those efforts it am joyed an 11% growth last year, the largest in china. the city is undergoing numerous nation wide development plans. older buildings still exist in the center of the city. built on a hilly region, flat land is scarce. buildings are conducted on slopes and there are steps everywhere. >> dai has been working as a bang bang since migrating here at the age of 15. he knows every bang bang in town. but in the past few years a lot of his peers have quit the profession and left town. >> the village where dai lives has been desi