In March 1809, Marshal Soult led a new French expedition that advanced south to the city of Porto before being repulsed by Portuguese-British troops and forced to withdraw.

He decided to strengthen the defences to the north of Lisbon by taking advantage of the hilly topography of that area.

In October 1809, he ordered the building of the Lines of Torres as a system of fortifications, redoubts, escarpments, dams and other interventions.

From October of that year it had a garrison of 100 Portuguese militia and gunners under the overall command of General Rowland Hill.

[1][2][6][7][8] The fort is close to a monument commemorating the role of the Torres Vedras Lines in the victory of the Anglo-Portuguese troops over the French armies.