As of November, there were 11 rail routes between 56 Chinese and 49 European cities. The first journey was made in March 2011, since when more than 10,000 trips have been completed.

Most journeys are between German and Chinese cities, but there are longer journeys; the longest of all runs between Yiwu and Madrid, a 12,874km route that holds the record for the longest in the world, ahead of the Yiwu to London branch.

The impetus for the development of the rail system has come from China, which presently runs a $176bn trade surplus with the EU.

However, Europe exports almost $200bn of goods to China a year, and there is currently a 350% annual increase in European goods making the return trip east by rail.

The rail links are now the basis of a China–Europe postal service.

A trip across the Eurasian landmass now takes about 16 days to complete, although it is thought that this could be cut to 14 days if Poland’s rail infrastructure were to be improved.

In particular, more cranes and storage space are required at Małaszewicze, a Polish village and dry port near the Belorussian border where trains have to switch from Russian broad gauge to European standard gauge.

The other break of gauge, at Khorgos on China’s border with Kazakhstan, is presently the biggest dry port in the world.

Over the past five years, China’s trade in goods with countries along the Belt and Road has exceeded $5.5 trillion, and China’s direct investment in the non-financial sectors of these countries reached $80bn during the same period.