Koufonisia is really two islands: Upper Koufonisia (Epano Koufonisia) and Lower Koufonisia (Kato Koufonisia). Koufonissia belongs to the Small Cyclades. Lower Koufonissia stretches from south-west to north-east, almost uninhabited, there are no sheltered bays, but there are a few anchorages on the south-east coast of the island, which provide good shelter from Meltemi for the yachts, but are open to the south winds. Upper Koufonissia is almost a circular island with a ferry port in the south of the island, with Parianos Harbor in the west, where the island's fishing fleet is concentrated.
Keros is an arid and harsh rocky uninhabited island that was one of the most important centers of the Cycladic civilization. Valuable archaeological finds have been discovered on Keros and the island is now protected by the state. The only possible anchorage is on the east of the island at Voulgari rock. This anchorage is accessible only in stable calm weather.
Recently, the islands are becoming increasingly popular because of the many good and still quite free beaches.