After the decline of Minoan Crete, the Achaians arrived at Kos. According to Homer, Kos, along with Nisyros, Karpathos, and Kalymnos, played an important part in the Trojan War. After the fall of Troy, Podarios, son of the God Asklepios and doctor from Thesaly, settled on the island after being shipwrecked. Podarios created the family of the Asklipidai, of which Hippocrates, the father of medicine, is the 18th descendant. Asklepeion stands at a distance of 4 km southwest of Kos town. Because of the slope of the ground, the buildings were erected on a number of levels, with steps between them. On the first level are the remains of a small temple and a fountain. In the center of the second level there are remains of the altar of Asklepios and those of a temple to Asklepios in the logical order. To the east are ruins of the temple of Apollo. On the highest level are the foundations and columns of a Doric temple to Asklepios. The name comes through ancient times from Asclepius, the son of Apollo and Koronis. According to myth, he learned medicine from the Centaur Hiron; he later became known among the people as a god of medicine, and they believed that he could heal gods and men. Asclepeia are referred to in history as sacred hospitals, and the Asclepieion of Kos was the best and most famous of its time. For you now, this is one of the most interesting archaeological places that you can see and visit, even if you are generally not interested in archaeology.

This temple was the most sacred in the Asklepeion. This Island has given the world Hippocrates, father of medicine; it looks like a huge floating garden. The city is built along a wide bay and catches the eye from the very first moment. Here we shall visit the Knights' Castle, an impressive medieval building; Freedom Square with its huge plane tree, under the shadow of which Hippocrates is said to have taught; also Roman homes, with marvelous mosaics; early Christian basilicas; and the Museum, with its statue of Hippocrates (4th century B.C.), and other fascinating items of Ancient, Hellenistic and Roman times. This historic tree, which is considered by many to be the oldest tree in Europe, stands in front of the entrance to the Knights' Castle. Its trunk has a circumference of approximately twelve meters, and, according to tradition, it was under this very tree that Hippocrates taught medicine to his students. Next to the Platanos, there is an ancient Sarcophagus, which, during the Turkish occupation, was used as a water trough for the nearby Mosque.

We can also see the Doric Temple of Venus, the Roman School of Music and the Castle, built c. 1450 - 1478 by the knights of St. John on the ruins of the ancient wall.

The Castle houses a small collection of Classical sculptures, as well as inscriptions of the Hellenistic, Roman, Byzantine and early Christian periods.

In the 11th century B.C., the Dorian's invaded Kos and expelled the Achaians. In the 7th century B.C., Kos entered a federation with six other cities in Asia Minor, Rhodes, Kalymnos and Nisyros. At the end of the 6th century, Darius, King of the Persians, (as did the other cities of Asia Minor) subdued Kos (as did the other cities of Asia Minor). In 479 B.C., the united Greek army liberated the island after the battle of Salamina where the Persian King Xerxes was defeated.

During the Peloponnesian war (431-404 B.C.), Kos allied itself with Athens. For this, the island paid a high tribute when the Spartan Commander Astochos invaded the island in 411 B.C. In 394 B.C., and after a treaty with Sparta, the Koans once again allied with Athens. Under the influence of Athens, democracy was introduced. The level of culture, education and economy during this period is very high. This continued until King Mansolos from Halikarnasos conquered the island in 358 B.C.

In 334 B.C., the island allied with Macedonia and Alexander the Great.

After 82 B.C., Kos became part of the Eastern colony of the Roman Empire and was granted special privileges. These privileges where lost during the reign of August, causing a period of stagnation. A terrible earthquake followed the decline in 27 B.C.

During the Byzantine period, Kos flourished as part of the Byzantine Empire. Due to its geographic position, the island was continuously attacked and subjected to the blind fanatics of the Arabs and Turks. In 1204 A.D., the Venetians occupied the island. In 1457 A.D., a powerful Turkish army looted the island. This lasted a short time due to the help of the allies of the island. After repeated attacks, the Turks conquered the island, which was finally subdued by Sultan Suleyman.

During the Turkish oppression the Koans never gave up their heroic resistance.

On May 5th, 1912, Italian troups invaded the island and expelled the Turks. In 1934, an earthquake destroyed 80% of the island. The Germans continued the occupation in 1943, with a short interval of 20 days when the Englishman Batalos ruled. During 18 months, the Koans suffered terribly until 1945 when the island came under British control. On March 7th, 1948, Kos was returned to Greece.