Alcobaça is a municipality and a city in the district of Leiria, in Portugal.The city grew along the valleys of the rivers Alcoa and Baça, from which it derives its name. The city of Alcobaça became notable after the first king of Portugal, Afonso Henriques, decided to build there a church to celebrate the conquest of Santarém to the Moors, in 1147. The church later evolved into the Monastery of Alcobaça, one of the most magnificent gothic monuments in the country.