Aroania, also known as Chelmos, Helmos and Khelmos (Greek: Αροάνεια, Aroaneia, or Χελμός, from South Slavic хълм, mountain), is a mountain range that spans about 15 to 20 km from north to south (north-east of Lykouria and about 10 km SW of Diakopto) and about 5 to 10 km from west to directly east of Kalavryta to the Achaia-Corinthia prefectural border.