Annamese Range

Behind the coastal plain near Huế, the Annamite Range rises as a long watershed between the South China Sea and the Mekong basin. Its eastern face is abrupt: short, closely spaced rivers carry water down to the sea through steep valleys, making movement inland difficult. The western face is gentler and broadens into plateaus before the land descends toward the Mekong. Most crests stand on the Laotian side, so the divide shifts between the two later states even as the mountains command both flanks.

Routes across the range are exceptional features. The Nape and Mụ Giạ passes offer passage through country that otherwise presents a continuous obstacle. The moist seasonal forests of the Annamites form a major ecoregion divided into northern and southern sections. They shelter the rare antelope-like saola, douc langurs, gaur and other distinctive animals.

Near Huế, the nearness of coast, high ridge and distant basin gives the landscape several distinct worlds within a short distance: maritime lowland, steep forested valley and the gentler plateau country beyond the crest. The chain extends about 1,100 kilometres through Laos, Vietnam and a small part of northeastern Cambodia, with the Phouane, Nakai and Bolaven plateaus forming its three main upland stages.