Dalian is located west of the Yellow Sea (Korea Bay) and east of Bohai Sea roughly in the middle of the Liaodong/Liaotung peninsula at its narrowest neck or isthmus.
In the early Tang Dynasty (618-907), the Dalian region was under the jurisdiction of Andong Prefecture in Jili state, and in the Liao Dynasty (916-1125), it was under the jurisdiction of Dong Jing Tong Liaoyang county.
Dalian was named Sanshan in the period of Weijin (220-420), San Shanpu in the Tang Dynasty (618-907), Sanshan Seaport in the Ming Dynasty (1368-1644), and Qing Niwakou in the Qing Dynasty (1644-1911).