It is a mountainous island, with highest peaks those of Pyrgos (732 m) and Profitis Ilias (500 m), although there are available cultivating valleys as well.
Until recently, the economy was based mainly on agriculture (cereals, olives, wine) and cattle-breeding. Nowadays the residents are involved with the tourism.
A traditional type of land cultivation, dating back to the 6th century BC, is the system of terraces, “pezoules”, created with the help of retaining walls made of dry stone and they allow the cultivation in lands with big gradient.
At the late 80s, Ios engaged in mass tourism reaching the top of the islands with the highest indicators of tourist development.