The Xên Mường Thanh Festival is one of the typical folk and spiritual festivals of the Thai people in Điện Biên, dating back to the 13th century, associated with Chief Lạn Chượng – the founder and builder of Mường Thanh. The festival not only expresses gratitude to the ancestors who established and protected the village, but also prays for favorable weather, bountiful harvests, and a prosperous and happy life. Traditionally, Xên Mường Thanh is held in the 2nd and 3rd lunar months, lasting 5 days, with unique rituals: procession from the house of the village head, offering prayers to the spirits in the sacred forest, erecting village pillars, performing sacrificial rites, and participating in traditional cultural and sporting activities. The festival also carries the educational meaning of "drinking water, remembering the source," commemorating the leaders, generals, and those who contributed to maintaining peace in the border villages. The festival is held in Dong Xen Luong Vang Ven, Na Pung village, Thanh Truong ward, Dien Bien Phu city (now Dien Bien Phu ward, Dien Bien province), considered by the locals as a sacred land with the auspicious "father river, mother mountain" landscape, beside the gentle Nam Rom river and a system of flowing streams, creating a unique scenery that connects people with nature. Currently, the Xen Muong Thanh - Dong Xen Luong Vang Ven historical site has been classified as a provincial-level historical site, becoming a highlight in the preservation and development of traditional cultural values, and contributing to attracting tourists to experience the unique spiritual culture of the Thai people in Dien Bien.