Started by Prof. Luís Krus in 2002, these Colloquia intend to be a space for discussion and interdisciplinary reflection around the study of the city of Lisbon during the medieval centuries. The commemorative evocation of the conquests of Lisbon in 1147 and of Alcácer do Sal in 1217 is the pretext for a broader debate around not only these events and their meaning and impact but also the wider context surrounding them and explains, in the diversity of ways that were designed and redesigned, both in the peninsular space and in the broader framework that linked the West and the East.