Yen Bai is a province located in Tay Bac, the northern part of northern-central Vietnam. It shares borders with six provinces which are Ha Giang province, Lao Cai province, Lai Chau province, Son La province, Phu Tho province, and Tuyen Quang province. The province covers an area of 6887.46 square kilometres and as of 2019 it had a population of 821,030 people.

Nghĩa Lộ is a town in Yên Bái Province, in the north-east region of Vietnam. It is bordered by Văn Chấn District and Trạm Tấu District. In 1951, the Viet Minh 312 Division fought French forces in the area as part of the First Indochina War. As of 2020, the district had a population of 68,206. The district covers an area of 107.78 km2.