A planned benefit of "Dragoon" was the usefulness of the port of Marseille. The rapid Allied advance after Operation Cobra and "Dragoon" slowed almost to a halt in September 1944 due to a critical lack of supplies, as thousands of tons of supplies were shunted to northwest France to compensate for the inadequacies of port facilities and land transport in northern Europe. Marseille and the southern French railways were brought back into service despite heavy damage to the port of Marseille and its railroad trunk lines. They became a significant supply route for the Allied advance into Germany, providing about a third of the Allied needs.