Racing against time to finish before morning rush hour, a team of 1,500 railway replaced a critical section of track in the heart of the Chinese city of Xian. Video has just been released of the six-hour operation done overnight on January 15, 2019. The city in the city in the northwestern province of Shaanxi is among many around China bracing for a rush of travellers as families gather for the Lunar New Year celebrations starting February 5.