Unloaded from the trucks, the cannons were to be transported through a chain of mountains without going through a valley, in order to cut through the foothills of the 1,100-meter-high Pu Pha Song mountain; then they were to descend again in the direction of the Pavie Piste, which linked Dien Bien Phu to Lai Chau, which they would cross near Ban To; then they were to scale another new height in order to position the battery at Ban Nghiu, from where they would fire on the French garrison at point-blank range.
