Battle of Almaraz

The Battle of Almaraz was fought during the Peninsular War on 18–19 May 1812, in which the Anglo-Portuguese Army under Lord Hill destroyed a French pontoon bridge across the River Tagus, in Almaraz, Spain. The bridge was protected by two French garrisons at either end.

The action was swift-moving, deceptive, and daring. The decisive result produced a substantial improvement in the Allied position by keeping French forces separated ahead of the imminent Battle of Salamanca.

By late April 1812, the Duke of Wellington had successfully captured the strategic border fortresses of Badajoz and Ciudad Rodrigo, commanding the two major routes between Spain and Portugal. He now prepared to advance into Spain with the largest army he had commanded to date, which was strong enough to take on any French army. There were two French armies in Spain, however: Marmont's Army of Portugal, garrisoned near Salamanca, and Soult's Army of the South. The Tagus River separated the two armies.

The only bridges over the Tagus were at Toledo, Talavera, Arzobispo, Almaraz, and Alcántara. The Alcántara Bridge had been destroyed by the Portuguese, under Col. Mayne, on 14 May 1809. The bridges at Toledo, Talavera, and Arzobispo were under French control, but according to Napier, the left bank of the Tagus at Talavera and Arzobispo was "so crowded by the rugged shoots of the Sierra de Guadalupe, that it may be broadly stated as impassable for an army". Any artillery and heavy baggage moving between the two armies would have to cross at Toledo or Almaraz.

The latter bridge, built by the city of Plasencia under the reign of Emperor Charles V in the 16th century and known by the local people as the Albalat Bridge, was partially destroyed by the Spanish on 14 March 1809, to prevent its use by the French. The Portuguese under Colonel Mayne destroyed the bridge at Alcantara on 14 May 1809, for the same reason. The French built a pontoon bridge in the autumn of 1809, just west of the Albalat bridge. It was about 200 metres long and built with heavy pontoons. The central span was a light boat, designed to be removed at night for security.

General Rowland Hill was detached with his 2nd Division to attack the pontoon bridge over the Tagus. His force, numbering around 6000 men with nine guns, was virtually the same as that which surprised Jean-Baptiste Girard at the Battle of Arroyo dos Molinos, in 1811. The task facing Hill was a considerable one as the bridge of boats was protected on both banks by strong earthworks. The southern end of the bridge was protected by a bridge-head that was overlooked by Fort Napoleon.

Fort Napoleon was a strong fort, capable of holding 450 men and situated atop a hill above a steep embankment. It was not a difficult climb for any attacking troops, however, and entry into the fort was eased slightly by two large scarps, rather like steps, which led onto the fort's ramparts. The rear of the fort sloped down to the bridge-head and was protected by a palisaded ditch and loop-holed tower that would act as the last place of refuge should Hill's men gain entry into the fort. On the northern bank of the Tagus stood Fort Ragusa, in which was stored all the garrison's supplies and ammunition. This five-sided fort also had a 25-foot high, loop-holed tower that was to be the last place of defence. This fort was also covered by a field work close to the bridge.

The French had further strengthened the position at the bridge by securing the main road from Trujillo at a point about six miles south of the bridge. Here, where the road ascends the Sierra de Mirabete, the pass was commanded by a castle around which the French had built a 12-foot-high (3.7 m) rampart that housed eight guns. This was connected to a fortified house close to the road by two small works, Forts Colbert and Senarmont. The mountains were impassable to any wheeled vehicles, and the only other pass through the mountains, La Cueva, was two miles to the east of Mirabete. The road on the southern side of the mountains was passable to vehicles, but once through the pass the road deteriorated into little more than a footpath.