The Spring Festival rush is arguably the largest of human migrations. It is getting larger each year as the population grows and - with increased prosperity - becomes more mobile.
This year an estimated 134 million Chinese are expected to travel by rail over the New Year holiday, which is the only time of year when the usually half-hidden migrant population emerges en masse to travel home. Another 7.3 million people, predominantly business people and middle-class tourists, will travel by air. Countless millions will board buses and ferries.
Officially, the holiday will be a seven-day affair next week, but given the strain on the mainland's transport facilities, the festival itself is unofficially spread over 40 days, beginning this year on January 9 and running until February 17.
Factories give their workers a jump-start by halting production a week or two before the holiday, and many will not reopen until mid-February.
Guangdong - and particularly Guangzhou railway station - sit at the hub of the migration. On the first day of this year's festival about 53,000 people left on 150-odd trains. 'There are more and more people here each day,' said one taxi driver last Friday as he inched his way through the crowds at the station.
In the run-up to the official holiday alone, 1.55 million people will leave Guangzhou by train, with the flow peaking at 130,000 over January 19 and 20.
A rigid pecking order has been established at the station.