Kea is the first island of the Cyclades when one sails from Athens or southern Attica. This proximity and the existence of many natural harbours were important in the prosperity of the island in many periods.The oldest site is Kephala, at the north of the island. This settlement together with its cemetery date to the Late Neolithic period. Despite an occupation that did not last more than 100 years, the site is of a major archaeological importance mainly because it belongs to the transition to the Bronze Age.
The site of Agia Irini, at the bay of Koresos, was first occupied at the same period as Kephala but life continued on for several more centuries. The first period of prosperity was during the Early Cycladic; in the Middle Bronze Age a fortification was was built at the same time as the so-called "temple". During the Late Cycladic period an extensive building program was executed. It includes an extensive network of streets as well as drainage system. The central building, "A", had several rooms, some of which were decorated with frescoes. It is likely that this was a building with administrative functions. In the Late Bronze Age temple large votive terracotta figurines were found; these represent an exceptional discovery of the Creto – Mycenaean World. The site was abandoned after an earthquake around 1450 BC. but the temple was partly reused from the EIA onwards.
At Kea as elsewhere in the Aegean world, the EIA is poorly represented. At Agia Irini the temple was partly reused, and down into the Classical period. The divinity worshiped was Dionysos.
By the LG - EA period the four city-states of Kea were founded: Karthaia, Koresia, Poioessa and Ioulis (the latter was in the middle of the island). They were all fortified and a dense network of towers completed the defensive system of the territory. The rural landscape was also dotted with farms or mines, the main resources of the island mainly in the Classic period.
At Ioulis one can still distinguish the double walls of the city; the fortifications of the acropolis were later reused by the medieval Kastro. Apart from these fortifications and an impressive sculpture of an archaic lion well outside the city walls, archaeological evidence is scarce. In fact, the lack of systematic archaeological research at Ioulis makes difficult to restore the religious landscape. Written sources mention a temple to Apollo and Aphrodite while Athena, Artemis, Hermes and Dionysos where worshiped here.
The third city of Koresia is located above the modern village of Livadi, at the NE coast of the island. This city has the peculiarity of having two citadels. The fortifications are well preserved. Within the fortified limits an Archaic temple has been excavated on the higher acropolis. It may have been dedicated to Apollo Sminthios mentioned at Koresia by Strabo.
Karthaia is located at the SE of the island, at the bay of Poles. The theatre of the city is currently excavated. The two major sanctuaries of the city are located on the heights of Aspri Vigla. The first temple is thought to have been dedicated to Athena, judging by the sculptures of the pediment; the second was probably dedicated to Apollo and dates around 530 BC. The site was abandoned in late antiquity, in the seventh century AD.
Poiiessa is located at the SW of the island, at the edge of a fertile valley. Inside the ancient fortifications are still visible some architectural remains as well as retaining walls. In fact very little can be said of the topography. The ancient harbour was located at the south part of the bay; some structures here could be identified as possible ship-sheds.
Concerning the sanctuaries of the towns of Koressos, Ioulis and Poiiessa on Kea, the basics have not changed since the 1990ies (see T. M. Whitelaw, J. L. Davis, The Polis Center of Koressos, in J. F. Cherry, J.L. Davis, E. Mantzourani (eds.), Landscape Archeology as Long-Term History, Northen Keos in the Cycladic Islands, Los Angeles 1991; and various articles in L. Mendoni & A. Mazarakis Ainian (eds.), Kea-Kythnos: History and Archaeology, Athens 1998). On Karthaia on the other hand, at the sites of the sanctuaries of Apollo and "Athena", the restoration works, conducted under the consecutive direction of V. Lambrinoudakis and E. Simantoni-Bournia between 2001-2009, have not only changed the appearance of the site but have also led to significant results allowing a better understanding of the history of the two urban sanctuaries. These have been published in a lavishly illustrated small book, written in three languages (Greek, English and French) (E. Simantoni-Bournia, L.G. Mendoni, T.-M. Panagou, Καρθαία ... ἐλαχύνωτον στέρνον χθονός..., Athens 2009). The restoration work within the Doric peripteral temple of "Athena" led to a better understanding of the three phases of the temenos and the edifice, from the late 6th century to the early 5th. Evidence beneath the pteron and the cella has proven that cult activities and a first retaining wall, date to at least the middle of the 6th century B.C. The Classical Doric propylon and Building D (a prostyle Doric building) were also restored. The latter presents two phases, dated in the 5th ("proto-D") and late 4th/early 3rd centuries B.C. The edifice may have been either a Prytaneion or a Bouleuterion. The restoration work at the temple of Apollo Pythios, also led to some interesting results. There were six columns in antis in the prostasis, and the order would have been Doric. A small side doorway was found at the end of the long North wall. The date of construction of the temple, ca. 530 BC, based until know on the architectural details, was confirmed by the discovery of pottery in its foundation trenches.
Caskey, M. E. 1986. The temple at Ayia Irini : the statues, Princeton (Keos : results of excavations conducted by the University of Cincinnati 2).
Cherry, J. F. 1991. Landscape archaeology as long-term history : Northern Keos in the Cycladic Islands from earliest settlement until modern, Los Angeles (Monumenta archaeologica 16).
Choremi, A., C. Vlassopoulou & G. Venieri. 2002. Κέα. Ιστορία και Αρχαιότητες, Athens.
Galani, G., L. Mendoni & C. Papageorgiadou. 1982. Επιφανειακή έρευνα της Κέας, Αρχαιογνωσία 3: 237-244.
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Manthos, K. 1991. Αρχαιολογία και Ιστορία της νήσου Κέας, Εισαγωγή – Μεταγραφή – Σχόλια, Mendoni, L. (ed.), Athènes.
Mendoni, L. G. & A. Mazarakis Ainian. 1998. Kea- Kythnos : history and archaeology : proceedingsof an international Symposium, Kea - Kythnos, 22-25 June 1994 (Μελετήματα 27), Athens.
Psyllas, I. 1921. Ιστορία της νήσου Κέας, Athina.
Simantoni-Bournia, E., L.G. Mendoni, T.-M. Panagou. 2009. Καρθαία ... ἐλαχύνωτον στέρνον χθονός..., Athens.