Tourists walk past the memorial of CPC's first congress in Shanghai Photo:Yang Hui/GT

Shanghai tourism sector regulator has asked all local tourism attractions to follow strict coronavirus prevention and control measures as the neighboring Nanjing city's Delta variant outbreak has spread to more than 20 cities in China.

East China's Nanjing, 300 kilometers north of Shanghai, reported 14 new locally transmitted virus cases on Saturday, including 12 cases with mild symptoms and 2 with common symptoms, according to the Nanjing Health Commission on Sunday.

Tourists have to show their health code, ID certification, appointment information before entering tourism sites, as a necessary way to make sure tourists' admission information can be traced. 

At Sihang Warehouse Memorial Museum in Shanghai, all the tourists have to show their health code and appointment information before entering into the memorial over the weekend.

Meanwhile, the staff workers at the museum were instructed to strengthen inspection of indoor venues and persuade the tourists to follow proper prevention measures if they don't wear face masks.

All travel agencies are required to strengthen prevention measures and avoid traveling in groups to high-risk areas.