Not far from Elounda, close to the Venetian salt pans, we find a few remains of the ancient city Olous (most are submerged in the sea) or Oloundas, which was inhabited since the Minoan period. Olous was one of the hundred most important cities of ancient Crete, with a maximum population of over 30,000 people. The administrative system of Olous was Eunomia, a form of democracy. In Olous, Tallean Zeus, Apollo, and Vritomartis (Artemis) were worshipped.

Olous minted its own coin. The historian Svoronos identified 11 different types of coins. Most of them depicted Vritomartis Artemis on one side and Zeus with an eagle, a dolphin, or a star on the other. The development of Olous continued until the first Byzantine period, as evidenced by the basilicas of Poros with their marvelous mosaics and the Basilica of Kolokytha with its exceptional white marble parts.