To investigate the developing tourism routes for linking cultural heritage sources on traditional festival by local, centering and celebrating of communities and traditions in the Northeast traditional festivals' region in Maekong River Basin were purposed. Associations with celebration and may also provide entertainment, particularly to local communities of cultural heritage sources were linked of tourism routes. These celebrations offered belonging to religious, social, and geographical groups, cultural also seek to inform members of their traditions among families and self-social communities. Collection data approach to surveys, interviews, observations, and focus group discussions with a sample of 85 people who consisted of the key, casual, and general informant groups in Nakhon Phanom, Mukdahan, Amnat Charoen, and Yasothon Provinces to management and promotion with faithful and believable were administered. The original festival are to believable and sanctity of ancient people, practicing inheritance and inherit were admired. The Buddhist temple and religious ceremonies were participated, such as the Illuminated Boat Procession, Nakhonphanom; the Boat Processional Racing, Mukdahan; Bunkhunlan inheritance, Yasothon. As for the development of the tourism routes for linking cultural heritage sources, according to the types of the trips and the requirements of the target tourist groups for 1-5 day trip, amazingly.Key words: Traditional festivals, development of tourism routes, linking cultural heritage sources, the catchment watershed, Mekong river basin. INTRODUCTION Background of Northeast Region on tradition, festival and local culture of ThailandThailand is an enchanting Buddhist Kingdom with a unique past. As a more detailed background to holiday in Thailand, this aims to give further details on the Kingdom as a whole, and more specifically on the Northeast of the country. Isan (also written as Isan, Issan, Esan or Esarn) is the Northeast Region of Thailand. It is located on the Khorat Plateau, bordered by the Mekong River to the north and east, and by Cambodia to the South. To the West, it is separated from Northern and Central Thailand Agriculture is the main economic activity, but due to the socio-economic conditions and hot, dry climate output lags behind that of other parts of the country. This is Thailand's poorest region. The main language of the region is Isan (which is similar to Laos), but Thai is also widespread and Khmer is spoken in the South. Most of the population is of Lao origin, but the region's incorporation into the modern Thai state has been largely successful. Prominent aspects of Isan culture include mor lam music, Muay Thai boxing, cock fighting and the food, in which sticky rice and chillies are prominent ( Figure 1(a)).Isan covers 62,000 square miles (160,000 square km). It is roughly coterminous with the Khorat Plateau, which tilts from the Phetchabun mountain range in the west of the region (the location of several national parks) down towards the Mekong River. The plateau cons...