Two islands in the southern Aigean Sea.
During the Trojan War, Pheidippos and Antiphos commanded the Achaian troops from Kasos, Krapathos, Nisyros, the city of Kos, and the Kalydnai.
According to the Geographer Strabo (Geography 10.5.19), the Kalydnai are presumed to be the islands of Leros and Kalymna, although the two islands are not mentioned by name in the Iliad.