Cripta Arqueológica do Castelo de Alcácer do Sal

Considered the largest archaeological crypt in the country, it is located beneath the Castle of Alcácer do Sal, now transformed into the Pousada D. Afonso II. It presents traces of the Iron Age dating from the 6th century BC, as well as structures from the Roman period and the Islamic occupation, covering a considerable area. Medieval walls from the post-Reconquista Christian era were also found, based partially on Roman walls which, in turn, overlap older pre-existing structures dating from the Iron Age.