Snake Tower from the outside. The Snake Tower derives its name from a carved snake at the lower entrance door. A group of three coats of arms at the upper entrance are: the leopard arms of Philibert de Naillac, French founder (1396-1421). The arms of the order. The hammer relief of Heinrich Schlegelholt, German architect of the castle. The tower basement dates back to Byzantine times. The tower was used as a hospital by the knights and the Ottomans.