Dien Bien Phu (Ðiện Biên Phủ) is a small town in northwestern Vietnam. It is best known as the site of the 1954 Battle of Dien Bien Phu, fought between the Viet Minh and France. The battle is significant in that it ended major French involvement in Indo-China, and led to the accords which partitioned Vietnam into North and South.

The town of Dien Bien Phu itself has a population of around 125,000, although it was much smaller at the time of the battle. The majority of the population is not ethnically Vietnamese - rather, Thai ethnic groups form the largest segment. Ethnic Vietnamese make up around a third of the population, with the remainder being Hmong, Si La, or others.

Dien Bien Phu lies in Muong Thanh valley, a 20-km-long and 6-km-wide basin sometimes described as "heart-shaped". It is the capital of Dien Bien province, and has traditionally been considered remote. It is only around 35 kilometers from the border with Laos.

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