ABSTRACT
In the northeast and southwest territories of Vietnam, there are two gulfs which hold very important geo-economic and geo-strategic positions. The Gulf of Tonkin had close historical, economic, and cultural relations with northeast Asian countries from time immemorial. Conversely on the western sea-area of the Gulf of Siam from the early centuries CE, the marine polity of Phù Nam (Funan) had established relations with territories in Southeast and South Asia.1 With an area of 126,250 sq km (36,000 sq miles), the Gulf of Tonkin is one of the largest gulfs in Southeast Asia. It is bounded by the Vietnamese and Chinese coasts in the west and north respectively, and the (Vietnamese) “East Sea”, that is the South China Sea in the south. The northeast coastal area of Vietnam, comprising ten provinces and cities extending to a length of 763 km, fronts a large part of the Gulf of Tonkin. Three Chinese provinces – Guangdong, Guangxi, and Hainan – in the nearby vicinity of the Gulf of Tonkin had centuries-long commercial, political, and cultural contacts and relations with Vietnam and other Southeast Asian countries. The Gulf of Tonkin, an important part of the South China Sea, with its
economic potentialities and rich cultural environment was the foundation for the famous maritime culture of Hạ Long. The cultural vestige of Hạ Long has been found not only on the northern area but also in the south and the middle of Vietnam. Hạ Long culture also extended its influence to South China, and mainland and insular Southeast Asia.2 In the process of establishment and development, Hạ Long culture established its wide relations with many countries in the region through commercial routes and the interlinking of islands.3
