The area of the archaeological site of ancient agora is successive to the port of Kos and is situated at the eastern end of the island.
After the ancient city of Kos had been established as the administrative center in 366 b.C., several public buildings and sanctuaries were constructed at the area both of the Agora and of the ancient port.
Both sites had been excavated by Italian archaeologists, after the strong earthquake of 1933, during which a considerable part of the old town collapsed. The excavated area covers the part of the ancient agora which was situated within the medieval fortification. The excavations started in 1935 and lasted until 1942. Along with the excavations, there were made several restoration works in some of the monuments of the agora and of the port. After the end of the World War to and the incorporation of Kos to the Greek State, the Greek Archaeological Service carried out a series of rescue excavations. The result of all this work, both of the Italians and of the Greeks, was to bring to light the administrative center of ancient Kos, a series of nice public buildings, sanctuaries and a part of the rest of the city.