5km south of Antimachia, has both Early Christian and ancient remains. The village and harbour, which provides a year-round ferry service across to Nisyros, have been engulfed by a disproportionate expansion of building and tourist infrastructure along the coast, leaving Kardamaina with little natural appeal beyond its sandy beaches and setting. In the process of this expansion evidence has come to light of no less than three Palaeochristian basilicas in the area. The floor-plan of the most accessible of these, the 5th century Aghia Theotis, is to be seen 50m northwest of the square beside the port in a block bounded by Kanari and Patmou Streets. It was a three-aisled basilica with narthex and baptistery to its west. The other two lay southwest of Kardamaina, on the site of the ancient city of Halasarna (reached by following the shore less than 1km along the road that crosses the watercourse just west of the town centre). The ancient settlement grew up between the shore and the bluff behind, which functioned as its acropolis. The site has only been partially uncovered and is pressed upon by modern construction; but it has already revealed some striking remains. There are several levels: most easily distinguish able by eye are the houses of the Early Christian era, which are built over the sharper, meticulous masonry of the Hellenistic buildings below. In the southwest corner is the lower part of a beautifully constructed, 2nd century bc marble public building (probably not a temple), whose base is constructed in an unusual red stone. North and east of this within the area, a 3rd century bc Temple of Apollo Halasarnas is being unearthed. At the upper level of excavation are the remains of houses, a basilica and a cemetery of the Early Christian era. On the far side of the acropolis hill, traces of the late Hellenistic theatre have been identified; the ruined apse of yet another EarlyChristian basilica, stands in the fields between the Apollon Hotel and the acropolis hill. Although systematic excavations by the University of Athens have only just begun to uncover the extent of the remains, it is clear that the whole area was densely inhabited in Antiquity.
Kos Island is part of the Dodecanese Island group