Commuters between Shanghai and its neighboring Suzhou of Jiangsu province have had a newly opened travel option since Saturday when Suzhou's Metro Line 11 went into operation.

The newly launched metro line of Suzhou connects with Shanghai's Metro Line 11 at Kunshan Huaqiao Station in Kunshan, a county-level city under the administration of Suzhou, allowing passengers seamless transfers between the two cities' metros.

This is the first time that the core cities in the Yangtze River Delta region have linked their separate urban subway systems, as part of the region's efforts to enhance transportation interconnection to further push the region's integration.

"The most convenient part of taking this new metro line is its flexibility, especially comparing with taking the high-speed train," said Meng Fan, a Suzhou resident who frequently travels to Shanghai. "The metro station is not that crowded, and we will not have to follow tight train schedules. If we change our travel plan at any time on the way, we can just get on and off the metro without too many concerns."

Lu Wenxue, general manager of Suzhou Rail Transit Group Co, Ltd, said Suzhou Metro Line 11 was planned as early as a decade ago, when the Kunshan Huaqiao Station, which served as the northern terminal of Shanghai Metro Line 11, started operation.

Shanghai Metro Line 11, the longest continuous operating subway line in the world, is also the country's first cross-provincial subway line. The line connects Kunshan of Suzhou with Shanghai's Jiading district and then continues southeast to pass through the city's Putuo, Xuhui and Pudong districts, ending at the Shanghai Disney Station.

"Suzhou Metro 11 is actually the city's sixth subway route, yet we named it Line 11 to sync with Shanghai's Metro Line 11, indicative of Suzhou's ambition to better integrate into the Yangtze River Delta region," Lu said.

According to Ding Chen, an official from the information office of Kunshan government, Huaqiao is home to nearly 100,000 residents, who are regular commuters between Kunshan and Shanghai.

"This new line allows them and other residents to travel more easily, as well as to gear up Kunshan's economic growth and integrated development as regional ties deepen," Ding said.

Notably, Kunshan has ranked first among China's top 100 county-level cities in terms of overall competitiveness for 18 consecutive years.

The launch of the intercity subway line, which runs through the investment-heavy Suzhou Industrial Park, also paves the way for further synergetic development of Suzhou and Shanghai. At present, many Fortune 500 enterprises have built their Chinese headquarters in Shanghai while placing their factories in Suzhou.

"As the region is turbocharging its development into the world's sixth-largest city cluster, more convenient intercity traffic is a must," He Jianhua, a researcher with the Shanghai Academy of Social Sciences, told Xinhua News Agency.

Shanghai's Metro Line 17, which is currently being extended to the west, will also connect with Suzhou's Metrol Line 10 in the coming years, according to published government plans.