Passengers wait for trains at the waiting hall of Harbin Railway Station in Harbin, northeast China's Heilongjiang province, Sept 29, 2023. Friday marks the Mid-Autumn Festival this year, followed by the National Day holiday from Sept 30 to Oct 6.  (PHOTO / XINHUA)

BEIJING – Hundreds of millions of trips are expected to be made in China during the eight-day public holiday, which officially started on Friday, authorities said.

The Mid-Autumn Festival and National Day holiday is the longest public holiday break since China optimized its COVID-19 response measures late last year.

On Friday, some 66 million cars were predicted to hit roads nationwide, the Ministry of Transport said.

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Topics involving traffic jams have been trending on social media.

Passengers run to the ticket gate at Tianjin West Railway Station in north China's Tianjin, Sept 29, 2023. (PHOTO / XINHUA)

Passengers wait for trains at the waiting hall of Chongqing North Railway Station in Chongqing, southwest China, Sept 29, 2023. (PHOTO / XINHUA)

Passengers walk on the south square of Harbin Railway Station in Harbin, northeast China's Heilongjiang Province, Sept 29, 2023. (PHOTO / XINHUA)

Netizens have posted video clips on microblogging service Sina Weibo, showing flyovers jammed with crawling cars. Some even shared videos showing people caught in highway traffic jams sitting by the side of the road playing mahjong.

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Some 190 million train trips are forecast to be made from Wednesday to Oct 8, which takes in the Mid-Autumn Festival on Friday and National Day on Sunday.

This Sept 29, 2023 photo shows passengers at Zhengzhou Railway Station in Zhengzhou, Central China's Henan province. (PHOTO / XINHUA)

Passengers are about to board a train at Chongqing North Railway Station in Chongqing, southwest China, Sept 29, 2023. (PHOTO / XINHUA)

Passengers are seen on a train at Beijing West Railway Station in Beijing, China, Sept 29, 2023. (PHOTO / XINHUA)

Passengers head to the waiting hall of Hankou Railway Station in Wuhan, central China's Hubei province, Sept 29, 2023. (PHOTO / XINHUA)

This aerial photo taken on Sept 29, 2023 shows passengers lining up to enter Hankou Railway Station in Wuhan, central China's Hubei province. (PHOTO / XINHUA)

Each day, 15 million people on average are expected to crisscross China via the country's sprawling railway network for sightseeing and family reunions, said the China State Railway Group. In 2019, 138 million rail trips were made during the same period, official data showed.

Friday was expected to seek the peak, with more than 20 million rail trips, the group said in a statement.

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The Ministry of Transport has forecast that a total of 490 million total trips would be made during the holiday travel rush, a 78.6 percent year-on-year increase.

Contact the writer at lilei@chinadaily.com.cn