What chain of mountains separate nothern and southern vietnam?

Question

What chain of mountains separate nothern and southern vietnam?

Answer 1

There isn't a chain of mountains that separate North and South Vietnam. The Ben Hai River (Sông Bến Hải) is considered the geographical border between North and South Vietnam.

The Annamite Mountain Range (Dãy Trường Sơn) is the predominant mountain range of Vietnam, but it lays North-South instead of East-West, which would be necessary to separate North and South Vietnam. However, the Annamite Mountain Range does separate Laos and parts of Cambodia from Vietnam.

Answer 2

Ho Chi Minh Hills.  That's a suburb of Ho Chi Mihn City near the mountains.