Aerial photo taken on June 30, 2017 shows the entrance of Wuxia Gorge, one of the Three Gorges on the Yangtze River, in southwest China's Chongqing. Located in southwest China, Chongqing is the only municipality in central and west China. Built on mountains and partially surrounded by the Yangtze and Jialing rivers, it is known as a "mountain city" and a "city on rivers". It serves as a major economic and cultural center in west China. With its special topographical features, Chongqing has the unique scenery of mountains, rivers, forests, springs, waterfalls, gorges, and caves. In recent years, Chongqing authorities uphold green development and have made great efforts in building ecological civilization in the municipality. From 25 to 27 in July, the "Chongqing Day" event is held at the ongoing Beijing International Horticultural Exhibition. The event will introduce the economic development, local products, tourist attractions and culture of Chongqing. (Xinhua/Liu Chan)