Physical geography and topography

Chongqing is situated at the transitional area between the Tibetan Plateau and the plain on the middle and lower reaches of the Yangtze River in the sub-tropical climate zone often swept by moist monsoons. It often rains at night in late spring and early summer, and thus the city is famous for its "night rain in the Ba Mountains", as described by poems throughout Chinese history including the famous Written on a Rainy Night-A Letter to the North by Li Shangyin.[40] The municipality reaches a maximum width of 470 km (290 mi) from east to west, and a maximum length of 450 km (280 mi) from north to south.[41] It borders the following provinces: Hubei in the east, Hunan in the southeast, Guizhou in the south, Sichuan in the west and northwest, and Shaanxi to the north in its northeast corner.[42]

Qutang Gorge on the Yangtze River

Chongqing covers a large area crisscrossed by rivers and mountains. The Daba Mountains stand in the north, the Wu Mountains in the east, the Wuling Mountains in the southeast, and the Dalou Mountains in the south. The whole area slopes down from north and south towards the Yangtze River valley, with sharp rises and falls. The area is featured by a large geological massif, of mountains and hills, with large sloping areas at different heights.[43] Typical karst landscape is common in this area, and stone forests, numerous collections of peaks, limestone caves and valleys can be found in many places. The Longshuixia Gap (龙水峡地缝), with its natural arch-bridges, has made the region a popular tourist attraction. The Yangtze River runs through the whole area from west to east, covering a course of 665 km (413 mi), cutting through the Wu Mountains at three places and forming the well-known Three Gorges: the Qutang, the Wuxia and the Xiling gorges.[44] Coming from northwest and running through "the Jialing Lesser Three Gorges" of Libi, Wentang and Guanyin, the Jialing River joins the Yangtze in Chongqing.[45]

Li Bai's Poem of Chongqing's Baidi Cheng

Leaving at dawn the White Emperor crowned with cloud,I've sailed a thousand li through canyons in a day.With the monkeys' adieus the riverbanks are loud,My skiff has left ten thousand mountains far away.

The central urban area of Chongqing, or Chongqing proper, is a city of unique features. Built on mountains and partially surrounded by the Yangtze and Jialing rivers, it is known as a "mountain city" and a "city on rivers".[46] The night scene of the city is very illuminated, with millions of lights and their reflection on the rivers. With its special topographical features, Chongqing has the unique scenery of mountains, rivers, forests, springs, waterfalls, gorges, and caves. Li Bai, a famous poet of the Tang dynasty, was inspired by the natural scenery and wrote this epigram.[47]

Specifically, the central urban area is located on a huge folding area. Yuzhong District, Nan'an District, Shapingba District and Jiangbei District are located right on a big syncline. And the "Southern Mountain of Chongqing" (Tongluo Mountain), along with the Zhongliang Mountain are two anticlines next to the syncline of downtown.[48]

Zhongliang Mountains (中梁山) and Tongluo Mountains (铜锣山) roughly forms the eastern and western boundaries of Chongqing's urban area. The highest point in downtown is the top of Eling Hill, which is a smaller syncline hill that separates the Yangtze River and Jialing River. The elevation of Eling Hill is 379 m (1,243 ft). The lowest point is Chaotian Gate, where the two rivers merge with each other. The altitude there is 160 m (520 ft). The average height of the area is 259 m (850 ft). However, there are several high mountains outside central Chongqing, such as the Wugong Ling Mountain, with the altitude of 1,709.4 m (5,608 ft), in Jiangjin.