XINING -- The Qinghai-Tibet Railway, the world's highest plateau railway, saw increased passengers and cargo in 2013, according to its operator.

The railway, which spans 1,956 km from Xining in the northwestern province of Qinghai, to Lhasa, regional capital of Tibet, carried 11.73 million passengers and 57.77 million tonnes of cargo in 2013, up 8.8 percent and 12.8 percent respectively year on year, said the Qinghai-Tibet Railway Company on Thursday.

The country's booming online trade left its mark on cargo transport in 2013, as more than 38.73 percent of the cargo transported came from online orders, according to the company.

The railway has proven effective in boosting business in Tibet since it began service in July 2006.

Official figures show Tibet's gross domestic product soared from 34.2 billion yuan ($5.4 billion) in 2006 to 80.2 billion yuan last year, an average annual growth of at least 10 percent.

The railway has also brought a surge of tourists, boosting Tibet's tourism, hospitality and manufacturing sectors.

In 2005, a year before the rail link opened, the autonomous region received 1.8 million tourists from home and abroad, while it received 12.9 million tourists in 2013, according to the regional tourism bureau.

Tourism revenues grew to 16.5 billion yuan in 2013 from 1.94 billion yuan in 2005, it added.

Meanwhile, the railway has attracted more and more pilgrims to Tibet.

Wang Tieshan has worked on the railway for more than five years as the conductor of train K9801 from Xining to Lhasa.

He told Xinhua that December to mid-January is the peak season for pilgrimages to Tibet, as pilgrims are free from farming and grazing.

"The train carries more than 400 pilgrims from Sichuan, Gansu, Qinghai and other provinces each time, many of whom are from the same family or the same

The company has begun to extend the railway in Tibet with the construction of a 253-km line linking Lhasa to Xigaze, a historical city in southwestern Tibet. The line is expected to be completed in 2014.