 The largest proportion of the sites is in the river valleys of northern Croatia, and the most significant cultures whose presence was discovered include Baden, Starčevo, and Vučedol cultures.The Iron Age left traces of the early Illyrian Hallstatt culture and the Celtic La Tène culture.Much later, the region was settled by Illyrians and Liburnians, while the first Greek colonies were established on the islands of Hvar, Korčula, and Vis.