It was a primitive oared boat dug out from a single tree trunk. The dugout inner part ensured excellent buoyancy and enabled the transportation of merchandise. Navigation was achieved with short, wide oars. As it evolved, it acquired a slightly raised prow with a ram and a bulky raised stern which were the main characteristics of the later ancient Greek warships. Its presence in Greece is indirectly denoted from the lead models of the monoxylon in Naxos (found in the Ashmolian Museum in Oxford) and from the remains of the lake monoxylon, 3.30 metres in length and some clay models that were found in the prehistoric settlement of Dispilio, Kastoria.
SOURCES: Harris Tzalas, Boats and Navigation in the Aegean (article).