The Castle of São Jorge (Portuguese: Castelo de São Jorge; Portuguese pronunciation: [kɐʃˈtɛlu dɨ sɐ̃w̃ ˈʒɔɾʒ(ɨ)]) is a Moorish castle occupying a commanding hilltop overlooking the historic centre of the Portuguese city of Lisbon and Tagus River. The strongly fortified citadel dates from medieval period of Portuguese history, and is one of the main tourist sites of Lisbon.