A raised highway cuts through the mountains of Sichuan in Southwest China. （PHOTO PROVIDED TO CHINA DAILY)

On a sweltering afternoon in 1996, Zhang Yunying, then a 44-year-old farmer, was furious with herself when she realized she had left her house keys at a store down the hill.

She was almost home when she realized, which meant it would take nearly two hours to walk back to the store and retrieve the keys, and even longer to get back to her hilltop home.

Back then, a narrow, steep and often muddy trail that passed through the hills was the only way for Zhang to reach the outside world.

"The trail leads to the county seat down the hill, where the villagers sell homegrown tea and buy groceries. My parents told me that it was also the main path for the transportation of salt long ago," Zhang said.

Her village lies above a deep mountain valley on the border between the southwestern provinces of Sichuan and Yunnan.

Many local trails, including the one Zhang took, were part of the Tea Horse Road, an ancient network of caravan paths that wound through the mountains.

A survey conducted by the State Council, China's Cabinet, and published in 2017 as part of the nation's first geographical census, showed that about 95 percent of Sichuan's land consists of mountains, plateaus or hills.

Those factors made it difficult to carve out roads for centuries.

That's why the trail Zhang took－dating from the Tang Dynasty (618-907)－was still in use until recently, although its poor condition and narrow width made it unsuitable for modern vehicles.

Villagers pick skullcap leaves in Zhaojue county, Sichuan.（PHOTO PROVIDED TO CHINA DAILY)

Hard times

Local resident Zhang Debin said: "It was hard for farmers to walk up and down with full baskets on their backs. Sometimes, they had to pay porters when the tea they grew was ripe."

The 43-year-old operates a tea-processing plant in Pingshan county, which is under the jurisdiction of Yibin, a mountain-encompassed city in southern Sichuan.

He said the only proper road for vehicles ran through Yibin, and while it was fine in good weather, mud made it impassible after rain.

"Poor transportation facilities affected communication with the outside world, and the inhabitants of this place lacked almost everything: food; clean water; gas; you name it," Zhang Debin said.

"In the past, the standard of living was low for many people in the county."

Until 1983, about 60 percent of county towns in the province were inaccessible to automobiles, so most places relied on human and animal power for transportation, he added.

A sealed road winds through mountains in the south of Sichuan. （PHOTO PROVIDED TO CHINA DAILY)

Migrant workers

Years ago, like many of his young peers, Zhang Debin wanted to make a decent living outside the county, so he became a migrant worker in the economically active coastal regions.

Sichuan's GDP growth rate was lower than the national average for 13 of the 20 years from 1980 to 2000. However, it was also the most populous province until Chongqing was designated a provincial-level municipality in 1997 and became a separate entity.

In the past 40 years, Sichuan has been China's largest exporter of migrant workers, while coastal Guangdong province has seen the largest inflow of such people.

By 1995, the year Zhang Debin went to work at a toy factory in Guangzhou, Guangdong's capital, six highways had been built in the province and a further seven were under construction.

It was also the year a highway was built in Sichuan, the first major road in western China.

"There were many large factories offering well-paid jobs in Guangdong, so it had become a friendly place for young people to work. It was also where I first heard the phrase, "Want to be rich? Build roads!" Zhang Debin said.

That became a battle cry in Sichuan when a growing number of decision-makers realized the poor infrastructure was impeding economic development in the province and forcing many people to leave.

During the Ninth Five-Year Plan (1996-2000), social and economic development initiatives helped the province expand its road construction program.

In the last year of the plan, the length of sealed roads in Sichuan reached 108,529 kilometers. Completion of 1,000 km of highways ranked Sichuan sixth in the country in terms of road length and first among the western provinces and regions.

After that, Sichuan's economy maintained double-digit growth for 12 consecutive years until 2001, while the rate exceeded the national average for 17 consecutive years.

"I felt that many things had started to change when I returned home for Spring Festival years later－for example, many people had TVs at home and some had even bought cars," Zhang Debin said.

Tourists cycle along a sealed road in a mountainous part of Sichuan province. （PHOTO PROVIDED TO CHINA DAILY)

Changing attitudes

One of the biggest changes is that young people in Sichuan now seem to have a different attitude toward leaving their hometowns.

In 2016, two years after graduating from a university in Chengdu, Sichuan's capital, He Xin applied for a civil service job in his hometown in a county in Yibin.

"I owned a new media studio in Yibin for two years, but it did not work out," he said.

"I knew local civil servants could earn a decent salary and they were able to practice what they preached, so I applied for a low-level position because of the fierce competition at the higher levels."

He was quickly dispatched to work in a village situated on the same hill as Zhang Yunying's home.

Nowadays, if Zhang Yunying leaves her keys at the store, it only takes 40 minutes for her to make a return journey by car to pick them up.

He Xin drives along the same road to the village where he works.

The journey only takes an hour, and it is difficult for him to understand the changes sealed roads have made to local residents' lives.

"I have heard from the senior staff that in days gone by almost no young university graduates wanted to work in the villages because they did not want to settle down on the mountain," He said.

Poor infrastructure had long impeded social and economic development, while growing urbanization resulted in declining populations in China's rural areas.

Now, working at the grassroots is a good option for people who want to avoid the fierce competition in big cities, according to He.

After the government decided to deepen rural development, more and more resources were poured into the antipoverty battle in the countryside, while reducing the cost and time of accessing job opportunities and social services became a priority.

From 2013 to 2017, the central government spent 400 billion yuan (US$61 billion) on building and upgrading rural roads, and now about 99 percent of the villages located on plateaus, deserts or grassland have access to roads.

Spending spree

In Sichuan, the government has spent 124.14 billion yuan building and upgrading 116,000 km of sealed roads in rural areas during the past five years.

This year, the total length of rural paved roads in the province reached 291,000 km, the most in the country.

Transportation in Pingshan has also seen significant changes. In 2015, all the county's villages were connected by sealed roads, and since last year, a reliable intervillage bus service has been provided for residents.

In 2016, Zhang Debin returned to Pingshan and opened his tea factory with the money he had saved as a migrant worker, even though he had originally planned to use it to buy a house in Guangzhou.

"Before, during the harvest season, the tea farmers even had to carry their tea down the hills at night using flashlights," he said.

"Now, whenever they are ready to do business, a truck will be waiting on the hill to carry the tea to my plant to process it."

The "Immortal Poet", Li Bai (701-762), who lived at the height of the ancient Tea Horse Road, once wrote, "The road to Shu is harder than scaling the skies!"

The "Shu" he mentioned is today's Sichuan, and the line is a vivid illustration of the inconvenience of transportation in the province centuries ago.

"Li may have walked the same trails the farmers used to take every day," Zhang Debin said.

"But as paved roads have now spread all over Sichuan, those old trails have entered the realms of history."