Item from March 21, 1999, in China Daily: A bicycle courier shows a guard his identification before entering a building in Beijing to deliver express mail.

Bike express mail services are growing fast in the capital. For just 10 yuan, parcels can be delivered anywhere in the city within a couple of hours.

China's courier services have grown steadily along with the exponential growth in e-commerce.

Last year, the number of packages delivered rose by more than 51 percent year-on-year to 31 billion, according to the State Post Bureau of China.

The industry's revenue during the same period reached 400 billion yuan ($58 billion), the bureau said.

By 2020, China is expected to become the world's largest express delivery market with an annual revenue of 800 billion yuan. Annual parcel deliveries are expected to top 50 billion by then.

SF Express, founded in 1993 in Guangdong province, is one of the largest private logistics firms in China. Last year, its revenue rose by 19.5 percent to 57.5 billion yuan.

Last month, it went public on the Shenzhen Stock Exchange, which made its CEO Wang Wei the third-richest man in China.

It costs about 13 yuan to deliver a 1-kilogram parcel in Beijing within one day, according to SF Express.

The country has about 19,000 courier companies with more than 1 million couriers delivering parcels every day.