Th?i k??B?c thu?c cu?i cùng k?t thúc sau chi?n th?ng tr??c nhà Minh c?a ngh?a quân Lam S?n.Roughly triangular in shape, with its northeast and southwest sides bounded by the northern uplands, the Crimson River delta extends inland some 150 miles (240 km) and operates some seventy five miles (one hundred twenty km) alongside the Gulf of Tonkin.