But the French were impeded along the Lines of Torres Vedras, a system of 152 fortifications north of Lisbon, planned by Wellington, supervised by Lieutenant-Colonel Richard Fletcher constructed by Portuguese laborers, manned by 40,000 Portuguese troops and members of the local population. Marshal Massena and his forces reached the lines by 14 October, but were unable to penetrate the defenses, and he was forced to retreat in April 1811. Supplies were running low, and Massena sent a request to Bonaparte for new instructions, but was compelled to withdraw before the instructions arrived, and he retreated to Santarém. Although Napoleon finally sent Soult, it was too late for Massena, who could not hold Santarém and withdrew towards Coimbra by March 6. Successively, the French were defeated in several smaller battles: the Battle of Sabugal, Fuentes de Onoro, Battle of Condeixa, Battle of Casal Novo, and the Battle of Foz de Arouce, in addition to Michel Ney's rear-guard action at the Battle of Pombal. With winter quickly approaching, his forces starving, they were again defeated at the Battle of Redinha and with Anglo-Portuguese forces in pursuit, Massena crossed the border into Spain; the War would continue until March 1814, but not on Portuguese territory.