Study of the fortified towns through their historical development and transformation Archaeological studies of the stratigraphy of the town show that habitation in the area of Chania coincided with the natural stronghold of Castelli Hill for about five millennia, from the Neolithic period to the Venetian age. This natural acropolis was the site of Minoan Cydonia, a major settlement with a palace complex in the centre and extensive graveyards on the outskirts. Despite the unending rivalry with neighbouring cities, Cydonia continued to flourish and expand (to the boundaries of the turn-of-the-20th century city) in the historical period, although no fortifications from this period have ever been identified. The first known fortification of the hill dates from the Hellenistic age; during the subsequent Roman and early Byzantine periods, the city was repeatedly destroyed and rebuilt within the same enclosure wall. As the seat of a bishopric with a rich agricultural hinterland, the city was refortified in the 6th or 7th century (according to recent research data) with a mighty wall, raised with material from the ruins of ancient Cydonia, which appears to have been destroyed. The contour of the Byzantine wall follows the line of the hill. It is irregular in shape, with a straight southern section, and encloses an area of about 3 hectares. Very little is known about the internal organisation of the settlement, which was destroyed by Saracens in 823. With the Byzantine liberation of Crete in 961, life resumed on the fortified hill; and the city continued to play its former role on account of its harbour, although it is possible that an attempt may have been made to relocate it to a safer position farther inland, and specifically to the new fort of Castellos, which was being built near Varypetro. With the Fourth Crusade, Crete was handed over to Bonifacius Montiferrati Marchio, who sold it to the Venetians in 1204. Once settled in Chania (1252), they proceeded to repair the fortifications, to afford them protection against local uprisings. At the same time, the layout of the city was redesigned: a broad central street - the Corso – was opened, and several cross streets created to link the city via its 4 gates with the harbour and the main provincial roads. Public buildings were erected, and houses and palaces built for the colonists and the nobility over the ruins of structures from earlier ages. Around the city a number of constructions were built: harbour installations, a round tower (torrione) to protect the harbour entrance and monasteries for the Catholic monastic orders. Illustrated maps from the 16th and 17th centuries provide considerable information about the shape of the city in that period. As the city prospered and the local population grew to regard the Venetians as protectors against the rising Ottoman menace, scattered settlements began to spring up around the fortified core. These gradually developed into suburbs, which were known as borghi. Construction of a second, more extensive, low enclosure wall to protect them began in the 14th century and continued into the 16th. The line of this wall appears on a later map of 1542. At this time the increasing threat of Ottoman attack against the Venetian colonies in the Eastern Mediterranean obliged Venice to reinforce the fortifications of the cities and other key strategic points on the island. To this end Veronese military engineer Michele Sanmicheli was commissioned to design and build new fortifications for Chania, Rethymno, Heraklion and other places. Construction of the new fortifications for Chania began in 1538 and was completed by the end of the century, although with numerous imperfections and deficiencies. The new wall followed the contemporary defensive principles of bastioned fortifications, and formed a quadrangle parallel to the shore and enclosing the harbour. The old fort of Castelli fell into disuse, and its walls and towers were gradually built up as the need for residential space increased. Also at this time, work was carried out to improve the harbour and reinforce the breakwater, and 17 dockyards (arsenali) were built to service shipping, while the water supply system was improved by the construction of reservoirs and the extension of the aqueduct. Chania now occupied an area of 40 hectares, and had a population of about 8000. The main streets in the city were straightened, and many mansions and houses for the people were built. Quite a number of the elements of the urban fabric of that period still exist today. The new fortifications, however, could not stop the Turks from taking the city in 1645, after a siege of just two months. The Turks retained the fortifications, repaired the breaches in the walls and made some minor additions. The urban fabric was slowly transformed, and the residential pattern changed. The Turks lived mainly in the eastern districts (Castelli and Splantza) and the Christians chiefly in the west (Topana), next to the small Jewish quarter. The Turks converted churches into mosques and built new ones, and added baths, fountains and khans. As the concentration of population within the confines of the fortifications increased, construction became denser and began to swallow up public spaces. It was not until the final years of the 19th century, when the city – numbering 13,000 souls in 1881 – was choking within the confines of the walls, that the Ottoman authorities permitted some construction outside the walls: cemeteries, dervish convents, small suburbs. From the early years of Cretan Independence (1898), and particularly after the island’s unification with Greece (1913), measures were taken for the development of the city outside the walls and part of the fortifications began to be torn down to allow communication between the areas inside and outside the walls and to provide space for modern uses. Fortunately, the way the walls were built and the need for unusual efforts to remove them resulted in the preservation of much of the enclosure wall. By the beginning of the 20th century the city covered 70 hectares, and had spread along the axis of the old rural roads around the Venetian walls. It continued to grow rapidly over the next several decades, and by 1961 its area had expanded to 275 hectares and its population to 33,211 inhabitants. In 1965 the area within the walls was declared an historic monument. Today, the city has a population of 72,000 (1991) and occupies an area of 445 hectares.