Gulf of Tonkin

The Gulf of Tonkin is a gulf at the northwestern portion of the South China Sea, located off the coasts of Tonkin (northern Vietnam) and South China. It has a total surface area of . It is defined in the west and northwest by the northern coastline of Vietnam down to the Hòn La Island, in the north by China's Guangxi Zhuang Autonomous Region, and to the east by the Leizhou Peninsula and Hainan Island. Description and etymology The name Tonkin, written "" in chữ Hán characters and in the Vietnamese alphabet, means "eastern capital", and is the former toponym for Hanoi, the present capital of Vietnam. It is not to be confused with Tokyo, which is also written "" and also means "eastern capital". During the French colonial era, the northern region of today’s Vietnam was called Tonkin. Bắc Bộ is the native Vietnamese name of Tonkin. The bay's Vietnamese and Chinese names – and , respectively – both mean "Northern Bay". The Gulf of Tonkin is a relatively shallow portion of the Pacific Ocean; the majority of the gulf's ocean floor is less than in depth, and no part of the gulf is submerged in more than of water.