The construction site of Guangzhou Metro Line 18, which will connect Guangzhou, Zhongshan, Zhuhai, and Qingyuan. [Photo/southcn.com]

The pattern for vertical and horizontal metro lines connecting the Guangdong-Hong Kong-Macao Greater Bay Area starting from Guangzhou has taken shape.

Guangzhou and Foshan have released the tender notices for Guangzhou Metro Line 28 in succession in May. The line is expected to connect cities near Guangzhou, namely Foshan and Dongguan.

The operating mileage of Guangzhou's metro lines currently exceeds over 500 kilometers, while the number was only 5.4 km 23 years ago.

"This line has reminded me of the railway networks in London," said Ma Xiangming, chief engineer of the Guangdong Urban and Rural Planning and Design Institute.

"The pattern will bring cities in the Greater Bay Area together. It will remarkably enhance Guangzhou's power of accumulation and radiation effects as a national central city and a comprehensive gateway city," added Ma.

In addition, the western extension session of Guangzhou Metro Line 7 will connect with Medi Dadao Station in Foshan's Shunde district, Guangzhou's Metro Line 4 will connect with Dongguan's Metro Line 1, and Guangzhou's Metro Line 18 will extend to Zhongshan, Zhuhai, and Qingyuan.

"The operation of these metro lines will further link Guangzhou, Foshan, and Dongguan in the future, boosting the regional development of the information economy and advanced manufacturing," said Ma.