This work proposes “the presence of Archimedes in Cephalonia and in Euripus Strait” and the optimal “Archimedean” exploitation of the Euripus tidal current and of the Cephalonia coastal paradox cross flowing continuously from Livadi Gulf to the Gulf of Sami. The present paper intends to prove the useful modern rediscovering of some old Archimedean ideas concerning spiral water wheel technologies under the form of new and efficient horizontal-axis Archimedean hydropower turbines.