The Forts of Serra da Aguieira (Hills of Aguieira) were three forts constructed within 100 metres of each other as part of the second line of defence of the so-called

Lines of Torres Vedras The Lines of Torres Vedras were lines of forts and other military defences built in secrecy to defend Lisbon during the Peninsular War. Named after the nearby town of Torres Vedras, they were ordered by Arthur Wellesley, Viscount Wellington, ...

, which were constructed by Anglo-Portuguese forces in 1810 in order to protect the Portuguese capital

Lisbon Lisbon (; pt, Lisboa ) is the capital and largest city of Portugal, with an estimated population of 544,851 within its administrative limits in an area of 100.05 km2. Grande Lisboa, Lisbon's urban area extends beyond the city's administr ...

from possible invasion by the French during the

Peninsular War The Peninsular War (1807–1814) was the military conflict fought in the Iberian Peninsula by Spain, Portugal, and the United Kingdom against the invading and occupying forces of the First French Empire during the Napoleonic Wars. In Spain ...

. The forts are situated in the municipality of

Vila Franca de Xira Vila Franca de Xira () is a city and municipality in the Lisbon District in Portugal. The population in 2021 was 137,659, in an area of 318.19 km2. Situated on both banks of the Tagus River, 32 km north-east of the Portuguese capital L ...

, in the

Lisbon District Lisbon District ( pt, Distrito de Lisboa, ) is a district located along the western coast of Portugal. The district capital is the city of Lisbon, which is also the national capital. From its creation until 1926, it included the area of the cur ...

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

. From north to south the three forts are the Fort of Aguieira, the Fort of Portela Grande, and the Fort of Portela Pequena.

History

Following the Treaty of Fontainebleau signed between France and Spain in October 1807, which provided for the invasion of Portugal, French troops under the command of General Junot entered Portugal, leading to a Portuguese request for support from the British. In July 1808 troops commanded by the

Duke of Wellington Arthur Wellesley, 1st Duke of Wellington, (1 May 1769 – 14 September 1852) was an Anglo-Irish soldier and Tory statesman who was one of the leading military and political figures of 19th-century Britain, serving twice as prime minister of ...

, at the time known as Arthur Wellesley, defeated French troops at the Battles of

Roliça Bombarral () is a municipality in the District of Leiria in Central Portugal. The population in 2011 was 13,193, in an area of . It includes four civil parishes ( pt, freguesia) that provide local services. History It is known that the area of ...

and

Vimeiro Vimeiro () is a freguesia (civil parish) in the municipality of Lourinhã in west-central Portugal. It is in the District of Lisboa. The population in 2011 was 1,470,Convention of Cintra The Convention of Cintra (or Sintra) was an agreement signed on 30 August 1808, during the Peninsular War. By the agreement, the defeated French were allowed to evacuate their troops from Portugal without further conflict. The Convention was sign ...

, which led to the evacuation of the French army from Portugal. In March 1809,

Marshal Soult Marshal General Jean-de-Dieu Soult, 1st Duke of Dalmatia, (; 29 March 1769 – 26 November 1851) was a French general and statesman, named Marshal of the Empire in 1804 and often called Marshal Soult. Soult was one of only six officers in Fren ...

led a new French expedition that advanced south to the city of

Porto Porto or Oporto () is the second-largest city in Portugal, the capital of the Porto District, and one of the Iberian Peninsula's major urban areas. Porto city proper, which is the entire municipality of Porto, is small compared to its metropol ...

before being repulsed by Portuguese-British troops and forced to withdraw. FortedaAguieira

The threat of a further invasions by the French led Wellington, on October 20, 1809, to order the secret construction of defensive lines in order to protect Lisbon from Napoléon Bonaparte's troops led by Marechal Masséna. A total of 152 military installations were constructed, armed with 534 cannon and garrisoned with about 34,000 troops. Each work was given a number and the three forts discussed here were Numbers 40-42. They were built at the top of the Aguieira mountain range, providing excellent views of the surrounding area and of the River

Tagus The Tagus ( ; es, Tajo ; pt, Tejo ; see #Name, below) is the longest river in the Iberian Peninsula. The river rises in the Montes Universales near Teruel, in mid-eastern Spain, flows , generally west with two main south-westward sections ...

Fort of Aguieira

Construction of this fort (Number 40) began in February 1810, following an irregular star-shaped design, and was completed before October. It is situated at an altitude of 280 metres. The fort was not fitted with cannon: instead it was garrisoned with 150 soldiers whose main task was to protect the other two forts and cover surrounding roads.

Fort of Portela Grande

Fort Number 41 was constructed at the same time as the Fort of Aguieira and had a garrison of 240 men. It supported defences along the Tagus, providing fire to the west, as well as to the east in order to provide cover for the

Fort of Casa The Fort of Casa was the most easterly of the forts and redoubts built in 1809-10 during the Peninsular War on the second line of the three defensive Lines of Torres Vedras aimed at protecting the capital of Portugal, Lisbon. It is situated in th ...

, which was lower down and closer to the river. Portela Grande dominated the Bucelas gorge and it could also exchange crossfire with the Fort of Arpim to the north-northwest. At an altitude of 274 metres the fort of Portela Grande was built as an irregular 11-sided polygon surrounded by a dry

moat A moat is a deep, broad ditch, either dry or filled with water, that is dug and surrounds a castle, fortification, building or town, historically to provide it with a preliminary line of defence. In some places moats evolved into more extensive ...

, with gun emplacements. It had five cannon. As with Portela Pequena, the Fort of Portela Grande had a stone-lined

magazine A magazine is a periodical publication, generally published on a regular schedule (often weekly or monthly), containing a variety of content. They are generally financed by advertising, purchase price, prepaid subscriptions, or by a combinatio ...

, which was unusual in the Lines of Torres Vedras where most of the magazines were wood lined. The fort is now topped by a survey marker. FortedaPortelaPequena

Fort of Portela Pequena

The Fort of Portela Pequena is a short walk from the Fort of Portela Grande and had similar objectives to cover possible invasion along roads and the River Tagus. “Pequena” means “small” in Portuguese but, with 350 troops, this fort (Number 42) had a garrison larger than the “large” fort. It had six cannon. Like Portela Grande it had a dry moat protected by escarpments.

References

External links