The center of the old city of Chongqing (chóng qìng 重庆) is almost completely encircled by the two arms of the Yangtze River (yáng zǐ jiāng 扬子江) and Jialing River (jiā líng jiāng 嘉陵江). Row upon row of buildings climb the hills beside the rivers, giving rise to its nickname the "city of hills (shān chéng 山城)" and the phrase "night views of the hilly city (shān chéng yè jǐng 山城夜景)" known well both in domestic and in overseas. observing the nocturnal scenes which form a colorful three-dimensional painting, with waves of the Yangtze and Jialing river glistering against moonlit, star spangled sky,is an amazing experience that you shall never miss. 
The nocturnal sight in Chongqing is splendid and beautiful. When night falls, the lights of a myriad families shine like stars, climbing to the sky, where they join the star-studded dome above, the flowing water and open sky each playing off the other's radiant beauty. The whole city is a sleepless city and looks like a splendid palace floating on water. When people get into the palace, they will completely swept by the feeling of the heaven permeating the earth.If possible, choose a day that is relatively clear, as little can be seen when the fog is heavy, the city government has undertaken an urban beatification project that requires all new buildings to be illuminated at night. The banks of both rivers are lit up with colourful strings of lights and can be seen from quite a distance.
Since the city is on the mountains and the mountains are the city, on the mountain you can not only enjoying the charming view, but also enjoy the wonderful evening night scenes. At night, climbing up onto one of the less-populated hills affords panoramic views of the city‘s night lights. Due to the city‘s hilly terrain, you can see a hierarchy of lights in all directions. Chongqing at night presents a wonderful scene. Lights in different colors sparkle and shine in layers and are reflected in the sparkling river, creating a mirage-like view. It‘s hard to tell the river and the lights.
There are several vantage points for observing this mountain city by both day and night : the Red Star Pavilion (hóng xīng tíng 红星亭) in the Pi Pa Shan Park (pí pá shān gōng yuán 枇杷山公园) and the Kan Sheng Pavilion (kàn shèng lóu 瞰胜楼), you can see lights around you in Goose Neck Park (é lǐng gōng yuán 鹅岭公园) in Yuzhong District (yú zhōng qū 渝中区), but the favourite is One Tree Hill (yī kē shù 一棵树) on South Mountain (nán shān 南山).
reference, from http://www.foreignercn.com/index.php?option=com_content&view=article&id=4786:night-view-of-chongqing&catid=67:travel-in-chongqing&Itemid=138
