The tiny, uninhabited islet of Keros is a protected archaeological site from which over 100 Early Cycladic figurines have been excavated in the 20th century. Among the findings are the famous harpist and flautist now on display in Athens National Archaeological Museum. The village of Ano Koufonisi is built on the ruins of a Roman settlement. In the years to follow, the residents of Koufonisia have suffered from pirate raids and in the years of German Occupancy in 40’s many of them migrated to Athens or abroad.

Koufonisia and Keros islet are in total 26 sq. km. with a total population of 366 residents. The islet of Keros is not inhabited. The islands closer to Koufonisia are Naxos on the northwest and Schinoussa on the southwest.