Our study is focused on the comparative research of the feasts dedicated to Poseidon at Miletus and its Pontic colonies. The Left Pontus colonies (Sinope, Tomis, Istros, but also Pantikapaion) inherited the cult of Poseidon Helikonios from their metropolis. At Istros, from the second century BC, Poseidon was venerated in the hypostasis of Ταῦρος (Taurus) by a cultural association whose members were called Ταυρεασταί. In the month of Ταυρεών, in Miletus and in his Pontic colonies, the Ταύρεα feast was celebrated in honor of Poseidon Ταῦρος. The Taurea feast is attested in Istros and indirectly at Sinope.