Photo taken on June 9, 2018 shows people watch a violin performance at night in Xi'an, capital of northwest China's Shaanxi Province. Night tour nowadays has become a new impetus to boost tourism of Xi'an, which has been attracting tourists with its renowned attractions including the Terracotta Warriors and Horses. (Xinhua/Shao Rui)

People take photos of the Dayan Pagoda at night in Xi'an, capital of northwest China's Shaanxi Province, April 19, 2018. Night tour nowadays has become a new impetus to boost tourism of Xi'an, which has been attracting tourists with its renowned attractions including the Terracotta Warriors and Horses. (Xinhua/Shao Rui)

Aerial photo taken on June 9, 2018 shows the night view of ancient complex in Xi'an, capital of northwest China's Shaanxi Province. Night tour nowadays has become a new impetus to boost tourism of Xi'an, which has been attracting tourists with its renowned attractions including the Terracotta Warriors and Horses. (Xinhua/Shao Rui)

A dock outside the main SCO summit building Photo: Li Hao/GT

People take a rest at a bakery at night in Xi'an, capital of northwest China's Shaanxi Province, June 9, 2018. Night tour nowadays has become a new impetus to boost tourism of Xi'an, which has been attracting tourists with its renowned attractions including the Terracotta Warriors and Horses.(Xinhua/Shao Rui)