China sent a record number of cargo trains to Europe last year as demand for such services continued to expand under Beijing’s new Silk Road ambitions.

A total of 6,300 trains made the journey from China and to Europe trip in 2018, an increase of 72 percent compared to the previous year, according to Chinese news. Of these, 2,690 trains made the return trip back to China, up 111 percent year-on-year.

Since 2011, China has sent more than 11,000 freight trains to Europe and back as part of its Belt and Road initiative, which seeks to boost China’s trade links with more than 80 countries in Asia, Europe and Africa.

Thanks to subsidies offered under the initiative, a total of 65 freight rail routes have been opened between Chinese cities and 44 cities in 15 European countries, compared to practically none ten years ago.

But while subsidies have made trains a compelling middle option that is cheaper than air cargo and faster than shipping by sea, they have also led to competition between Chinese cities in launching new routes and concerns about the sustainability and efficiency of the business in the long run.

In a bid to improve the efficiency and commercial viability of Europe-bound train services, the Chinese authorities have announced plans to limit subsidies to no more than 50 percent of costs and then gradually reduce them.

The China Railway Corporation said it would focus on developing the China-Europe freight rail service in 2019 and promoting overseas and international railway projects under the Belt and Road initiative.