Vang Vieng

Vang Vieng lies beside the Nam Song, beneath steep limestone mountains in the uplands north of Vientiane. The river winds through a valley framed by cliffs and sharply rising karst peaks. Rainwater has dissolved the limestone over long ages, forming caves within the hills, while the Nam Song carries water south toward the Nam Ngum and the Mekong basin. Fields and villages occupy the flatter ground beside the river.