The fortified enclosure of the Venetian Fortress (today Heraklion) of the 15th century, which is still preserved today, is one of the most significant monuments of its kind in the whole Mediterranean basin. Another important monument of the period is the imposing fortress of "Koules" which is dominating at the edge of the Venetian NW breakwater of the old harbour. It was built by the Venetians before the construction of the new Venetian fortification, in order to protect the pier and the port (Figure 46). It took its last shape in the years 1523-1540, replacing another construction destroyed by an earthquake. The violent waves of the sea have been constantly causing damages to its stonework and foundation, thus it has been continuously repaired.