Pha Din Pass

Pha Din Pass is a 32 km mountain pass on National Highway 6 between Tuan Giao District, Dien Bien Province and Thuan Chau District, Son La Province, with a summit around 1,648 meters above sea level. Recognized as one of Vietnam's Four Great Mountain Passes, it is noted for its winding road, panoramic highland scenery, and historic role as a supply route during the 1954 Dien Bien Phu Campaign, now marked by a memorial relic site at the summit.

Visitors can expect a winding mountain road along National Highway 6 with steep curves and panoramic views over forested hills and valleys. At the summit area there is a Pha Din Pass Historical Relic site with a monument, stele and viewing platforms where visitors can stop for sightseeing and photography. The surroundings are highland landscape with scattered ethnic Thai villages, roadside stalls and often misty conditions.

Pha Din Pass was a key section of the supply route on National Highway 6 during the Dien Bien Phu Campaign in 1953-1954. Artillery, provisions and supplies were transported over the pass to the Dien Bien Phu valley. The summit area is now preserved as the Pha Din Pass Historical Relic site with a monument commemorating the transport efforts.

The pass lies in an area inhabited by Thai and other ethnic groups and is regarded as a symbolic gateway between the northwestern highlands and the Dien Bien basin. It is celebrated in Vietnamese literature and songs as an iconic northwestern mountain pass.