Dalian is a major sub-provincial port city in Liaoning province, People's Republic of China, and is Liaoning's second largest city and the third-most populous city of Northeast China. Located on the southern tip of the Liaodong peninsula, it is the southernmost city in both Liaoning and the entire Northeast. Dalian borders the prefectural cities of Yingkou and Anshan to the north and Dandong to the northeast, and also shares maritime boundaries with Qinhuangdao and Huludao across the Liaodong Bay to west and northwest, Yantai and Weihai on the Shandong peninsula across the Bohai Strait to the south, and North Korea across the Korea Bay to the east.

A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Hamburg, Manchester and Duluth; these access the sea via rivers or canals. Because of their roles as ports of entry for immigrants as well as soldiers in wartime, many port cities have experienced dramatic multi-ethnic and multicultural changes throughout their histories.