Laos, the most mountainous region, echoes the
of the Yunnan
fan some 500 km further south. The
of the Mekong follow a NE-SW
that of the upper Irrawadi
River, while the Nam
Ma follows a NW-SE
direction, like the eastern basin of
Red River. Only the Xiengkhuang
of Jars at its center, disrupts this fan pattern.
radiating in all directions, it binds northern Laos
Cordillera. The cordillera
Valley from the coastal plains of Central Vietnam
provides the junction with the Bolovens
of the Vietnamese plateaux.
The Mekong Valley is undergoing abrupt changes
direction in relation to its general meridian orientation,
in the North, and
in the region of
Beginning as a narrow corridor in the north, the
then broadens into a series of plains between
although these are less expansive
those on the Thai bank. The Laotian plains broaden out
the region of Savannakhet,
before being hemmed in
in by the southern plateau. The differences in relief
the plains along the Mekong disrupt navigation.
is notably restricted by the rapids of Khemmarat,
of Savannakhet, and blocked altogether by the Khone
at the Cambodian
of settlement on the three main plains along
river: Vientiane, Savannakhet and Champassack.
by the Lao ethnic group exceeds 50% almost
to the south. It surpasses
to Vientiane, and from the districts
province to the Cambodian border.
proportion of Lao is just over 18% in the highlands
and Vientiane and in Khammouane
in the Center, creating a break between the
of the North and South.