Authorities in China say that conditions have returned to ‘normal’ after a 100 km traffic jam which lasted 9 days. The record gridlock, which took place on the main highway between Beijing and Mongolia, was caused by a combination of roadworks and high traffic volumes. The motorway is part of the Beijing to Tibet expressway, and is heavily used by freight trucks carrying coal from Inner Mongolia. The road works were required to repair damage caused by an increase in cargo lorries using the highway. Although China has invested heavily in road building in recent years, there has also been a huge increase in both freight and passenger traffic.