Workers work in a tunnel of Metro Line 18 in Guangzhou, south China's Guangdong Province, April 20, 2021. Track construction was completed on Tuesday from Wanqingsha to Xiancun village, marking a major progress for the Metro Line 18 in Guangzhou, the fastest metro line within Guangdong-Hong Kong-Macao Greater Bay Area with a maximum designed speed of 160 km per hour. (Xinhua/Liu Dawei)
