The Nam Ou (Laotian: ນ້ຳອູ [nâːm ùː], literally: "rice bowl river") is one of the most important rivers of Laos. It runs 448 km from Phongsaly Province to Luang Prabang Province[1]. Along with the Mekong, the Nam Ou is the only natural channel suitable for large-draft boat transportation. Near its confluence with the Mekong are the Pak Ou Caves, famous for their Buddha statues.