Epirus (; , Ípeiros), formally the Epirus Region (Περιφέρεια Ηπείρου, Periféreia Ipeírou), is a traditional geographic and modern administrative region in northwestern Greece. It borders the regions of West Macedonia and Thessaly to the east, West Greece to the south, the Ionian Sea and Ionian Islands to the west and Albania to the north. The region has an area of about . It is part of the wider historical region of Epirus, which overlaps modern Albania and Greece but lies mostly within Greek territory.