Aerial photo taken on Aug. 21, 2019 shows the D6622 train leaves Caofeidian East Railway Station for Beijing South Railway Station in Tangshan City, north China's Hebei Province. Bullet trains running between Beijing and Caofeidian, with a stopover in Tangshan, officially started operation on Wednesday. Photo:Xinhua

People get on the D6622 train at Caofeidian East Railway Station in Tangshan City, north China's Hebei Province, Aug. 21, 2019. Bullet trains running between Beijing and Caofeidian, with a stopover in Tangshan, officially started operation on Wednesday. Photo:Xinhua

People takes photos as the D6622 train enters the Caofeidian East Railway Station in Tangshan City, north China's Hebei Province, Aug. 21, 2019. Bullet trains running between Beijing and Caofeidian, with a stopover in Tangshan, officially started operation on Wednesday.Photo:Xinhua

The D6622 train is ready to leave Caofeidian East Railway Station for Beijing South Railway Station in Tangshan City, north China's Hebei Province, Aug. 21, 2019. Bullet trains running between Beijing and Caofeidian, with a stopover in Tangshan, officially started operation on Wednesday. Photo:Xinhua