National Route 51 (Vietnamese: Quốc lộ 51) is a four-lane highway starting from the city of Biên Hòa to Vung Tau in Dong Nam Bo, Vietnam, passing Bình, Long Thành, Bà Rịa town. This is the backbone route linking Ba Ria-Vung Tau Province with Dong Nai Province and Ho Chi Minh City. With a total length of 85.6 km , with of 15 to 23 km, this road includes 15 bridges, going through several important industrial parks of the Principal Economic Area of South Vietnam, an area which includes province in South East Vienam region. The towns along this road includes: Long Thanh (where Long Thanh International Airport is under construction), Tam An Town, Nhon Trach City, Phu My Town (an important electricity hub of Vietnam). This national road starts from the roundabout in Bien Hoa city, 20 km north-east of Saigon Bridge of Ho Chi Minh City.