Passengers ride a subway train themed on the 19th National Congress of the Communist Party of China in Xiamen, East China's Fujian province, on Oct 9, 2017. The city's new Line 1 started test operations on Oct 6. [Photo/Chinadaily]

Subway line 1 runs on the Jixing Seawall in Xiamen, East China's Fujian province, Oct 11, 2017. It was the last day of the 6-day test operation of the subway line 1 that spans the sea in Xiamen.[Photo/Xinhua]

Passengers wait for trains of subway line 1 in Xiamen, Fujian province, Oct 10, 2017. [Photo/VCG]