Castle of Alenquer

The Castle of Alenquer is a medieval fortress located in the civil parish of Alenquer, within the Lisbon district of Portugal. Originally established as a Muslim fortress known as an alcaçova following the conquest of the territory in 714, the site features architectural remnants such as rectangular towers that display clear Muslim influences. The structure was captured by Christian forces under King Afonso Henriques after a two-month siege around 1160, marking the beginning of its transformation into a key defensive installation for the northern Lisbon region.

Historically, the castle played a pivotal role in royal disputes during the early 13th century. King Sancho I constructed a royal palace on the grounds and gifted it to his daughter, Infanta Sancha. Following a conflict with her brother, King Afonso II, Sancha took refuge within the castle walls in 1212, leading to a siege by royal forces. To resolve this familial and political standoff, Pope Innocent III placed the castle under the administration of the Knights Templar in 1216, underscoring its significant military and strategic importance during this era.

Today, the Castle of Alenquer is owned by the Portuguese Republic and remains open to the public. While the original fortifications have evolved over centuries, the site currently preserves historic walls and includes a small chapel dedicated to Nossa Senhora da Conceição. It stands as a testament to the region's complex history of Moorish occupation, Christian reconquest, and medieval royal intrigue, serving as a cultural landmark within the municipality of Alenquer.