Liao River in the context of "Loess"

The Liao Civilization or Liao River Civilization (Chinese: 遼河文明), named after the Liao River, is an umbrella term for several ancient civilizations that originated in the Liao basin. It is thought to have first formed in 6,200 BC. This civilization was discovered when Ryuzo Torii, a Japanese archaeologist, discovered the Hongshan culture in 1908.

The Liaodong or Liaotung Peninsula (simplified Chinese: 辽东半岛; traditional Chinese: 遼東半島; pinyin: Liáodōng Bàndǎo) is a peninsula in southern Liaoning province in Northeast China, and makes up the southwestern coastal half of the Liaodong region. It is located between the mouths of the Daliao River (the historical lower section of the Liao River) in the west and the Yalu River in the east, and encompasses the territories of the whole sub-provincial city of Dalian and parts of prefectural cities of Yingkou, Anshan and Dandong.

The word "Liaodong" literally means "Liao region's east", referring initially to the Warring States period Yan commandery of Liaodong, which encompassed an area from modern Liaoning-Jilin border in the north to the Chongchon River on the Korean Peninsula in the south, and from just east of the Qian Mountains to a now-disappeared large wetland between the western banks of middle Liao River and the base of Yiwulü Mountain, historically known as the "Liao Mire" (遼澤, Liáo zé) roughly in between the modern Xinmin, Liaozhong, Tai'an, Panshan and Beizhen). The modern usage of "Liaodong", however, simply refers to the half of Liaoning province to the left/east bank of the Liao/Daliao River.

The Northeast China Plain (simplified Chinese: 东北平原; traditional Chinese: 東北平原; pinyin: Dōngběi Píngyuán), also known as Songliao Plain, Manchurian Plain, or Northeast Plain, is located in Northeast China. It lies between the Greater and Lesser Khingan and Changbai mountains, ending at the coast at Liaodong Bay in the Bohai Sea. Covering 350,000 km, it is China's largest plain, with an elevation of lower than 200 meters, and less than 100 meters to the southwest. The Songhua, Nen, and Liao Rivers run through the plain.

The Northeast Plain includes Songnen Plain in the north, Liaohe Plain in the south, and Sanjiang Plain in the northeast. The Songnen Plain was formed by the Songhua and alluvial soils from the Nen. The Liaohe Plain, located in the hilly areas near Changchun, was created by the separation of watersheds of the Songhua and Liao, which are collectively known as the Liaohe Plain. The Sanjiang Plain, at the confluence of the Songhua, Amur, and Ussuri Rivers, was originally a swamp known as the "Great Northern Wilderness", becoming a food-producing area after reclamation. The original wetland area of the Sanjiang Plain has been greatly reduced.

Liaodong Bay is largest and longest of the three main bays of the Bohai Sea, the innermost gulf of the Yellow Sea. The other two bays are Laizhou Bay to the south and Bohai Bay to the southwest.

Although named after the Liaodong Peninsula (which forms its eastern shore), the bay is located directly south of the Liaoxi region, almost entirely west of the Liao River. It is bounded by the coastline of cities from southern Liaoning province (Dalian, Yingkou, Panjin, Jinzhou and Huludao) and eastern Hebei province (Qinhuangdao and Tangshan), between the Laotieshan Cape at Dalian's Lüshunkou District in the east, and the Daqing River estuary (which is an old southern mouth of Luan River) at Tangshan's Laoting County in the west. The bay is a source of ecological importance and exhibits rich biodiversity.

The Daliao River (simplified Chinese: 大辽河; traditional Chinese: 大遼河; pinyin: Dàliáohé, "Great Liao River") is a major river system in eastern Liaoning province of Northeast China, and formerly the main distributary of the lower Liao River until 1958. The Daliao River proper is formed from the confluence of three rivers at the border between Anshan's Haicheng city and Panjin's Panshan County, after where it runs a length of 94 kilometres (58 mi) covering a catchment area of 1,926 square kilometres (744 sq mi), before coursing in meanders southwest and draining into the Liaodong Bay just west of Yingkou.

The principal river of southern Northeast China, the Liao River, historically bifurcates into two distributaries near the Liujianfang Hydrological Station (六间房水文站) at Xinkaihe Town (新开河镇) of Anshan's Tai'an County, forming the Liao River Delta. The eastern distributary, called the Wailiao River, was originally the larger one and the main body of lower Liao River. It travelled southwards to pick up two large tributaries the Hun River and Taizi River, at a confluence locally referred as the "Trident River" (三岔河). After the three rivers merged, the resultant large river then adopted the new name as Daliao River.

Liaodong Commandery (Chinese: 遼東郡) was a commandery in imperial China that existed from the Warring States period to the Northern dynasties. It was located in modern Liaoning, to the east of the Liao River.

The commandery was created by the state of Yan on its northern border during the Warring States period. In Western Han dynasty, It administered 18 counties, including Xiangping (襄平), Xinchang (新昌), Wulü (無慮), Wangping (望平), Fang (房), Houcheng (候城), Liaodui (遼隊), Liaoyang (遼陽), Xiandu (險瀆), Jujiu (居就), Gaoxian (高顯), Anshi (安市), Wuci (武次), Pingguo (平郭), Xi'anping (西安平), Wen (文), Fanhan (番汗), and Dashi (沓氏). In 2 AD, the population was 272,539, in 55,972 households. In Eastern Han, 11 counties remained, including Xiangping, Xinchang, Wulü, Wangping, Houcheng, Anshi, Pingguo, Xi'anshi, Wen, Fanhan and Dashi. In 140 AD, the population was 64,158 households. During the reign of Emperor Xian, management of Buyeo affairs was transferred from Xuantu Commandery to Liaodong. In the Cao Wei dynasty, Xiangping in Liaodong became the seat of an office known as the "Colonel of the Dongyi" (東夷校尉), which was in charge of the military and relationships with the local peoples. In early Western Jin, the territory became the Liaodong Principality (遼東國). In 280 AD, the commandery had 8 counties, and a population of 5,400 households. A number of new commanderies was established in the region throughout the Sixteen Kingdoms and Northern dynasties periods, and by the time of Northern Wei, Liaodong only consisted of 2 counties, namely Xiangping and Xinchang. It was eventually dissolved during Northern Qi.

The Lower Xiajiadian culture (simplified Chinese: 夏家店下层文化; traditional Chinese: 夏家店下層文化; pinyin: Xiàjiādiàn xiàcéng wénhuà; 2200–1600 BC) is an archaeological culture in Northeast China, found mainly in southeastern Inner Mongolia, northern Hebei, and western Liaoning, China. Subsistence was based on millet farming supplemented with animal husbandry and hunting. Archaeological sites have yielded the remains of pigs, dogs, sheep, and cattle. The culture built permanent settlements and achieved relatively high population densities. The population levels reached by the Lower Xiajiadian culture in the Chifeng region would not be matched until the Liao Dynasty. The culture was preceded by the Hongshan culture, through the transitional Xiaoheyan culture. The type site is represented by the lower layer at Xiajiadian in Chifeng, Inner Mongolia.

Archaeogenetic data shows that "the West Liao River Valley was a contact zone between northern steppe tribes and the Central Plain farming population. The formation and development of the Lower Xiajiadian Culture population was likely a complex process affected by admixture of ethnically different people". The Lower Xiajiadian culture remains displayed high genetic affinity to "Yellow River farmers" but were not identical to them, in contrast, the Upper Xiajiadian remains displayed high genetic affinity to Ancient Northeast Asian Amur hunter-gatherers and later Xianbei. Archaeological and DNA evidence supports examples that the people of the Lower Xiajiadian Culture immigrating to the south and contributed to the gene pool of the Central Plain population during the Bronze Age.