The Spring Festival holiday travel rush is on in China. Millions of people are making their way home for family reunions to celebrate the Lunar New Year in the world's largest annual human migration. Many of China's 1.3 billion people work in big cities hundreds of miles from their home towns, and the week-long national holiday is the only time in the year that they will see their families.

China Year of the Monkey
Passengers wait to board a train at Shanghai Hongqiao Railway Station during the travel rushAly Song/Reuters
Chinese New Year travel
Passengers wait to board a train at a railway station, in Ningbo, Zhejiang provinceReuters
Chinese New Year travel
People carry their belongings toward trains at the main railway station in Guangzhou, Guangdong provinceAlex Lee/Reuters
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Passengers take escalators towards their trains in BeijingFred Dufour/AFP
Chinese New Year travel
Passengers wait to board their trains at the main railway station in Shanghai as they head to their home towns for the Lunar New Year holidayJohannes Eisele/AFP
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Passengers queue up to get their tickets at a railway station in Hefei, east China's Anhui provinceAFP
China Year of the Monkey
Motorcyclists head home from Zhaoqing, Guangdong provinceReuters

When the 40-day travel frenzy ends on 3 March, the estimated total volume of passengers is expected to reach more than 2.91 billion, an increase of 3.6% on last year. There will be about 2.48 billion journeys by road, 332 million by railway, 54.55 million trips by air and 42.8 million by water during this period, according to official estimates.

China Year of the Monkey
A woman holds her children's hands in front of a railway station in Beijing before boarding their train for the Spring FestivalKim Kyung-Hoon/Reuters
Chinese New Year travel
A woman pulls her daughter on a trolley before catching a train from Beijing to their home town for the Spring FestivalFred Dufour/AFP
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A woman pulls her daughter on a suitcase as crowds head home from ShanghaiAly Song/Reuters
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A mother feeds her son as they wait to board their train in ShanghaiJohannes Eisele/AFP
Chinese New Year travel
A man carrying a giant teddy bear heads home from Beijing West Railway StationJason Lee/Reuters
China Year of the Monkey
A teddy bear sits on a suitcase outside a railway station in BeijingKim Kyung-Hoon/Reuters
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Passengers arrive at a Beijing railway station as migration for the annual Spring Festival beginsDamir Sagolj/Reuters

China Railway Corporation says it plans to run nearly 15 percent more trains this year than it did last year, but many travellers said they still had trouble getting tickets for the days they wanted.

Heavy snow added pressure onto an already overloaded system as thousands of passengers were stranded at railway stations in Shanghai and Hangzhou. In central China, airports also faced problems, with the airport in Wuhan reporting the cancellation of 67 flights on Sunday (31 January). Along with trains and flights being delayed, numerous motorways were blocked by heavy traffic.

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People wait to enter Guangzhou Railway Station in Guangdong province, where more than 50,000 passengers were stranded because of weather delaysLin Hongxian/Reuters
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Passengers crowd at the waiting hall inside a railway station in Hangzhou, Zhejiang province, after trains were delayed due to heavy snowChina Daily/Reuters
Chinese New Year travel
Passengers crowd to seek refunds on their tickets at a counter after trains were delayed due to heavy snow, in Hangzhou, Zhejiang provinceChina Daily/Reuters
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People carrying luggage leave a railway station as snow falls in Wuhan, Hubei province,Reuters
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A man carries luggages through heavy snow as he leaves a railway station in Jiujiang, Jiangxi provinceChina Daily/Reuters
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A couple share a duvet at midnight at a railway station in Guangzhou, Guangdong provinceChina Daily/Reuters

Chinese families traditionally get together for a reunion dinner with their loved ones on New Year's Eve and let off fireworks in the streets.

The New Year, also known as the Lunar New Year or the Spring Festival, is marked by the lunisolar Chinese calendar. This means the date changes every year, but mostly falls between 21 January and 20 February in the Gregorian calendar. Festivities usually start the day before the New Year and continue until the Lantern Festival, celebrated on the 15th day of the new year.

Chinese New Year travel
A passenger sleeps on his baggage inside a train from Shanghai to ShijiazhuangAly Song/Reuters
China Year of the Monkey
A woman sleeps outside a railway station in Beijing before heading home for the holidaysKim Kyung-Hoon/Reuters
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Passengers wait to board trains for their home towns at a Shanghai railway stationJohannes Eisele/AFP
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A passenger sleeps on seats while waiting for a flight at Hong Kong International AirportChina FotoPress/Getty Images
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Passengers sleep in a waiting room at Hefei railway stationAFP
China Year of the Monkey
A man sleeps on his belongings outside a railway station in BeijingKim Kyung-Hoon/Reuters
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Passengers carry luggage as they enter the waiting hall of the Beijing West Railway StationJason Lee/Reuters
China Year of the Monkey
A man carries his possessions in a sack as he walks towards the Beijing railway stationKim Kyung-Hoon/Reuters
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A man carries a bag on his back in Guangzhou, Guangdong provinceReuters
Chinese New Year travel
A man waves goodbye to his family from inside a train at Hefei railway stationAFP
Chinese New Year travel
Travellers head home from Beijing for the New Year holidayFred Dufour/AFP

This year will welcome in the year of the monkey, part of an ancient tradition in which the Chinese zodiac attaches animal signs to each lunar year in a cycle of 12 years. The Chinese zodiac is separated into 12 blocks, each of which have a time-length of one year instead of one month like the western equivalent. The monkey is the ninth animal in the cycle, which will not take place again until 2028. Next year will mark the year of the rooster.