Bus from Sapa to Bien bien

Bus from Sapa to Dien Bien Phu.How to get to Dien Bien Phu? (you can see it above on the map), something like 300 kilometers away but nothing less than a 7hr journey due to the terrible quality of the mountain road you take. Bus from Sapa to Dien Bien Depart: 07.30 AM or 19.00PM