Nong Khai (หนองคาย) is a city in Isaan. The city lies on the west bank of the Mekong River, only 20 km from Vientiane, the capital of Laos.
Known as the Naga City (Nagas being the giant serpent guardians said to inhabit the Mekong River - see below) and famed for its lovely position on the Mekong, Nong Khai is a bustling Thai town and the gateway to Laos and Vientiane. It has many beautiful features which attract a considerable number of Thai and foreign visitors every year, including Sala Keaw Khu the almost surreal sculpture park; the enormously revered Luang Por Phra Sai Buddha Image which has a remarkable history; the truly extraordinary Phu Phra Bat Historical Park (though in Udon Province it is easily reached from Nong Khai); and the Thai-Lao Indochina Market called Tha Sadet Market which occupies many streets in the centre of town. A large part of the centre of town, including the river bank, has been made pedestrian-only. The Thai-Lao Friendship Bridge, opened in Apr 1994, was the first bridge across the lower Mekong, and only the second on the full course of the Mekong.