Urban rail transit in Chinese cities witnessed a steady growth both in operating scale and passenger traffic last year, according to a recent report from the China Association of Metros.

As of the end of last year, 40 cities in the Chinese mainland operated 208 urban rail transit lines with a total length of 6,736.2 kilometers.

In terms of operation scale, a total of 18 cities reached 100 kilometers or above, with 809.9 kilometers in Shanghai and 771.8 kilometers in Beijing.

Metro is the major form of all urban rail transit, which took 76.8 percent at 5,180.6 kilometers in operation, while commuter express took 11.2 percent with 754.6 kilometers by the end of 2019.

The top 10 cities for operation length of metro lines are Shanghai, Beijing, Guangzhou, Wuhan, Shenzhen, Chengdu, Chongqing, Tianjin, Nanjing and Suzhou.

Fifteen cities saw over 1 million passengers in their average daily passenger traffic. Among them, Beijing and Shanghai handled 10.87 million and 10.64 million passengers respectively.

The 10 cities with the most average daily passenger traffic are those with the largest economic and urban population size, the report said. Besides Beijing and Shanghai, the cities with the most daily passengers are Guangzhou, Shenzhen, Chengdu, Wuhan, Nanjing, Chongqing, Xi'an and Hangzhou.

For cities with the most crowded metros, Guangzhou took first place, followed by Shenzhen, Xi'an, Beijing, Shanghai and Hangzhou.

Besides, while Beijing, Shanghai and Guangzhou are way ahead in the operating mileage of urban rail transit, second-tier cities such as Chengdu, Hangzhou and Wuhan are racing to catch up with the former three cities in completed investment last year and rail under construction, said the news outlet Yicai citing the report on Thursday.