Customs staff members check the first "Qilu" freight train running from Jiaozhou, east China's Shandong province to Baku, capital of Azerbaijan in Jiaozhou, Jan. 31, 2021. A freight train carrying 100 twenty-foot equivalent unit (TEU) containers' goods such as tires and air conditions left Jiaozhou on Sunday, marking the launch of "Qilu" freight train services from Jiaozhou to Baku. [Photo/Xinhua]

Aerial photo taken on Jan. 31, 2021 shows the first "Qilu" freight train running from Jiaozhou, east China's Shandong province, to Baku, capital of Azerbaijan in Jiaozhou, Jan. 31, 2021. A freight train carrying 100 twenty-foot equivalent unit (TEU) containers' goods such as tires and air conditions left Jiaozhou on Sunday, marking the launch of "Qilu" freight train services from Jiaozhou to Baku. [Photo/Xinhua]

Customs staff members check the first "Qilu" freight train running from Jiaozhou, east China's Shandong province to Baku, capital of Azerbaijan in Jiaozhou, Jan. 31, 2021. A freight train carrying 100 twenty-foot equivalent unit (TEU) containers' goods such as tires and air conditions left Jiaozhou on Sunday, marking the launch of "Qilu" freight train services from Jiaozhou to Baku. [Photo/Xinhua]

Aerial photo taken on Jan. 31, 2021 shows the first "Qilu" freight train running from Jiaozhou, east China's Shandong province, to Baku, capital of Azerbaijan in Jiaozhou, Jan. 31, 2021. A freight train carrying 100 twenty-foot equivalent unit (TEU) containers' goods such as tires and air conditions left Jiaozhou on Sunday, marking the launch of "Qilu" freight train services from Jiaozhou to Baku. [Photo/Xinhua]