The fortress of Agios Nikolaos is a single stronghold that occupies the northern tip of the homonymous pier. It includes consecutive reinforcements and expansions after the destructions it suffered from sieges, during which it acted as “a key to the defense of the city”. The last 15 years an integrated reconstruction intervention for the restoration and enhancement of the medieval fortress has been carried out, in order to render it safe to be visited, by taking the necessary safety measures for visitors. As part of the interventions, comprehensive interdisciplinary studies have been elaborated and related articles have been published, which may be consulted by those interested in gaining insight into this particular subject.
The medieval city of Rhodes grew with successive expansions of the 7th-century AD early Byzantine castle, around the rocky elevation of the ground and between the two central ancient ports, occupying the geographical center of the glorious –Hippodamian- Hellenistic city. A characteristic feature is considered the formation of the military port Mandraki and the complex of ancient dockyards that almost reached the north wall of the Byzantine acropolis –which later became the palace of the Grand Master, at the site of the present moat. The gradual opening and widening of the moat to the west and south during the Byzantine and Knights period was apparently combined with the methodical quarrying of living rock below the ancient city level. Evidence of quarrying can be seen scattered along the flanks of the moat, particularly on the rock surviving to this day north of the bastion of Hagios Georgios (Saint George), thus preserving important elements of the ancient city infrastructure.
Of particular interest is the development of the dockyards area and the area of the two, out of five, main ports of ancient Rhodes that remained in use during the medieval times. It should be noted that all three piers of these ports preserve remains of prior formation and apparently coincide with the respective ancient ones. It is worth emphasizing that the dynamic design of the ancient city’s Hippodamian urban planning network can be seen in the organization of the medieval settlement. Moreover, in the wider region remain to this day the main access routes to the settlement. Along the axes of these routes “moved” the gates of the walled parts of the settlement from antiquity to this day.
The aforementioned process of successive expansions of the Byzantine fortification walls towards the two ports was completed in 1464 with the construction of the fortress probably on the site of the homonymous church of Agios Nikolaos (Saint Nicholas), at the edge of the ancient pier on the peninsula. The outline of the northeastern part of the castle’s Byzantine fortification is not entirely clear, even though parts of Byzantine masonry are detected at the base of the subsequent fortification structures of the early Knights era in the area. Besides, it is a fact that the imposing foursquare tower of Naillac, which was built around 1400 at the edge of the homonymous pier but collapsed in 1863 after a destructive earthquake, was abutted on a marble sloping base made of an ancient construction material in second use.
Therefore, an initial attempt to fortify the pier that controls the two main ports is identified and it is the respective pier of the Byzantine castle – acropolis, when the construction of the very high main tower built for the fortification of the ports was completed by the Grand Master Naillac. The next Grand Master Antoni Fluvian is to be thanked for the construction of the initial Knights pier, which gave access to the first floor of the tower through the insertion of an arched structure, an independent spiral staircase and a wooden lift bridge. The early gate, which existed at the same period with the pier, linked Emporiko -the “grand harbor”- with Mandraki and the pier of Agios Nikolaos prior to the construction of the polygonal surrounding wall of the tower of Saint Paul the Apostle and before the modification of its original route after 1440.
The shape of the foursquare tower of Naillac answers perfectly the purpose of the war tactics that precede the widespread use of cannons after the introduction of gunpowder in warfare around the mid-15th century. Its base is protected by an also foursquare surrounding wall, on the eastern side of which survives the special formation for placing the chain that closed the entrance to the port.
Until 1444, when the city was besieged by the Arabs of Egypt, the piers of Myli (Mills) and Agios Nikolaos remained unfortified. At the pier of the Mills the structure of the Hellenistic pier was preserved and the pier itself expanded further north at a time indeterminate, but in any case prior to the construction of the tower and its semi-circular surrounding wall during the era of the Grand Master Lastic (in 1451). By the end of the century, more than thirteen windmills were already operating, to which the characteristic stairs seen in the fairly later illustration by Breydenbach (1483) correspond.
The port piers
The pier of Agios Nikolaos ended north to a rocky platform, which the medieval tradition indicated as the location of the Colossus of Rhodes. It is the Hellenistic pier of the secondary port of Mandraki –a military port of the ancient city of Rhodes- stretching north (N) over a length of approximately 500 m. Alongside remains of the ancient pier on segments of natural rock that had been supplemented with large boulders survive to this day, while on its northernmost part to the east (E) a part of the ancient wharf-breakwater is preserved almost intact. The imposing fortress of Agios Nikolaos is where the pier ends and it abuts on a natural widening of the land on a rock, upon which there can be seen evidence of methodical quarrying, most likely from the medieval period. The abundance of marble elements, which can be seen scattered in the area of the medieval fortress or integrated as its structural components in second use, is attributed to an earlier Hellenistic structure of a yet unknown destination. Until 1464 there was only one church dedicated to Saint Nicholas, which is already mentioned in 1394 and is depicted in a miniature by Buondelmonti in Liber Insularum in 1420 with the inscription “Sanctus Nicolaus”. On the eastern flank of the pier three windmills survive until today. They postdate the windmills of the pier of the Mills and their construction dates after 1420 and before 1483.