♪ in china, there are groups of carriers called bang bang from the chinese word for poem

they were given this name because they carry anything with one pole over their shoulders. they have always been a vital part of people's lives here. in a city so full of hills and narrow roads. they've carried many roads for residents. now, they're on the verge of disappearing. >> the city used to have 500 of these carriers, as the city developed they're steady disappearing. this episode follows the end of their legacy.

the changjong river is the longest in china. it's a directly controlled municipality of china. it used to be a pt szechuan province but wasiven its current designation in 1997. as part of an effort to develop innercities that had fallen behind coastal regions due to the effects of reform policies. recently, it's being further developed as a hub connecting china and europe. thanks to those efforts, they

saw an economic growth, the largest in china. older buildings still exist in the center of the city. >> built on a hilly region, flat land is scarce. there are slopes everywhere.

this man has been working as a bang bang since migrating here at the age of 15. he knows every bang bang in town many in the past few years a lot of his peers have quit the profession and left town.

the village where he lives has been designated for redevelopment. many homes are being taken down and residents are decreasing in number. other than moving related jobs, his work load has dropped to below half that a year ago. to increase his earnings, he began buying people's old tools and selling them to tool shops. being in his 50s, he says he can't imagine changing jobs. he relies on his strength, earning up to 30 u.s. dollars a day, no matter how hard they work. due to these conditions, he's worked nonstop and bought a home for his family. on this this day, he carried wardrobe chests and a stone

mortar that his friend gave him for free. unable to judge the value, he settles for whatever price the stores offer. >> he received $20 for the two items, much higher than he expected. he didn't get any delivery jobs that day. there is no guarantee he'll find work the next day either.

the town that he has worked in for 35 years is disappearing and he hasn't decided where he will move to. on the walls of empty homes is a slogan urging people to move above a building being taken down. a drone hovers.

>> he showed us footage that he took with the drone. >> some 30,000 people once lived downtown. many street vendors used to line the narrow traditional streets. drawing crowds all day.

bang bang's carried heavy luggage through those crowds. when all the buildings are taken down, this area is scheduled to become a commercial district. roads wide enough for cars will be built. reducing the need for bang bang s. however, there is a place where many bang bangs do get work. the fruit and vegetable market in the center of town

zhou became a bang bang when he migrated here from szechuan province. his first job of the day is always to deliver wholesale produce to retailers in the market. >> zhou's job begins waiting for the delivery door to open. he'll be carrying one ton of bean sprouts to five stores by 6:00 a.m. joe makes about $7 for this job. it's not much, but it's guaranteed income. he can't afford to lose this job.

>> for one delivery, two people carry two buckets, weighing a total of 100 kilograms. from the entrance of the market to the very back of the store is about 100 meters. there are stores on the second floor as well. joe delivers to every single store.

>> the more deliveries, the more it leaves him out of breath, with a pained expression >> two and a half hours after the job began. joe finishes delivering the bean sprouts. he never once took a slightly past 6:00 a.m. as the market opens. joe's next job begins.

♪ >> most early morning shoppers are working in the dining industry. joe takes orders from them and carries goods to the parking lot or to nearby stores. fee malbang bangs which are hardly seen any more, can be seen working at this market. how many deliveries can be made depends largely on how many times they can move through the crowd. every bang bang is eager to do as many rounds as possible. zhou takes routes in a are

avoided by other bang bangs, this means less income for them. he feels the role of a bang bang is to meet the customer's needs. >> zhou has lunch around 11:00 a.m., he eats lunch around the same time every day. he orders a cup of rice porridge

for 7 cents. he says eating any more will make him sick during work. after a light lunch, zhou completes three more deliveries, he gets home around 2:00 p.m. >> joe lives in an apartment located five minutes on foot from the market. he lived here with his wife, son and daughters until two years ago, but his life changed greatly in this past year. his daughter graduated high school and left for vocational school. his son who works at a construction site got married. so now he lives with his daughter-in-law. this year, zhou and his wife got

their much wanted grandchild they aren't wealthy, but they can get by together as a family.

>> zhou goes back to the market at 5:00 p.m. and carries goods until 9:00 p.m. despite this exhausting work load, he makes just $15 a day.

♪ >> one man founded a company with 20 bang bangs 18 years ago. he only became a bang bang to make a living. conditions of his peers, he called on friends in hopes of improving the livelihood and social status of bang bangs. his company was the first one founded by bang bangs. in in just three years he was able to buy his own office

>> when the media buzz faded, work for bang bangs decreased. sales eventually declined. >> he decided to give up his job as a bang bang and make an effort to start a full scale transportation business.

>> he kept the company name bang bang and uses a truck instead of a pole. truck delivery is completely

different from being a bang bang, he had to start from scratch. some of his staff began complaining about the unfamiliar work and quitting. now his transportation company has grown large enough to move the offices of major companies. this is a business district. liu opened a new office here in hopes of expanding his business. he has doubled his original staff to over 50 employees. liu is working toward the 20th anniversary of his company's founding.

he intents to collect actual poles used by bang bangs. >> liu hopes to display poles that saw extensive use. he heads to a place where he used to come in search of work as a bang bang about he says it looks nothing like it was before.

there are no bang bangs in sight. the only people here are shoppers and tourists.

>> the poles are like partners for bang bangs. the longer they use them, the more memories they carry. they can't easily let go of them. >> liu believes the profession of the bang bang is destined to fade away.

>> with heavy poles digging into their shoulders, the bang bangs climb hills and weave through

back allies. there are said to be around 3,000 left. most all in their 50s. by 2017, the city of changching will have spent millions of dollars on urban improvement. narrow streets will soon be a thing of the past. and when the city has been transformed, what will be left for the bang bangs to carry. and where will they

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