China has one of the longest borders among world countries. The picture reflects sustainable friendship with neighbour countries. It shows the Detian Waterfall - Asia's largest transnational waterfall which is a joint treasure of China and Vietnam. One part belongs to China, another to Vietnam. During the trip, I saw a rainbow started from the Chinese side and going to Vietnam. Like a growing economy of China, the waterfall streams' power accents the importance of collaboration and establishing friendly relations with neighbours. The photo was taken with my phone Huawei P10 in September 2018: f/2.2 - 1/1502 sec - ISO 50