The islands have been constantly inhabited since prehistoric times and they have flourished in culture and trade. The early advance of Cycladic Civilization takes place in the islands of Cyclades with significant sites in Santorini and later in Classical period in the sacred island of Delos, next to Mykonos. The islands because of the diversity of the landscape and the position of each one of them have developed different kinds of goods and products but almost all of them have established trading through sea. The Aegean islands have been occupied several times by Venetians, Crusaders, pirates, Turks, Italians and their residents have suffer oppression and economic decline. In recent years, the islanders try to reinvent their economy by tourism industry.