Much like Venice, the centre of Cork City is built upon marshy islands located within the tidal estuary of the River Lee (1). Indeed the name for the city is derived from the Irish - ‘Corcach Mor Mumhan’ which means the great marsh of Munster and refers to the fact that the centre of the city is built on a series of islands surrounded by the River Lee. The origins of the built settlement lie in the early seventh century, with the establishment of a monastic settlement on the south channel of the river. Traditionally Saint Finbarr has been credited with the foundation of the monastery of Cork. The monastery, which was built on elevated ground on the south bank of the River Lee, is the earliest human settlement in Cork for which there is incontrovertible evidence. The date of the foundation is unknown but historians place it in either the sixth or seventh century.
Between the ninth and the tenth centuries this settlement became involved in the extensive Scandinavian trade network, and by the twelfth century its population appears to have comprised of native Irish and Hiberno-Vikings. At this time the trade of the embryonic City and Port of Cork was effectively controlled by the McCarthy Kings of Desmond. The MacCarthys built a residence and fortress near Cork. In Latin this fortress was called 'vetus castellarum' which is an exact translation of the Irish ‘sean dún’, or old fort, and corresponds with the present-day Shandon area of Cork (Burke, 2007a).
The fortified town was captured by the Anglo Normans in 1177, who enclosed it with a wall and defensive towers and created a medieval city with quaysides, markets and a main thoroughfare (modern day North and South Main Streets (2)). Over time, this wall was extended and the entire medieval city centre became one of the great walled towns of Ireland. The wall around the south island was composed mainly of limestone while the wall around the north island was composed mainly of sandstone.
Figure 1: Pacata Hibernia Map 1585-1600 showing Medieval Cork
Source: Cork City Council Libraries, 2007.
 Modern day North and South Main Streets are shown on the east-west axis as shown. The modern day Docklands are located just out of the picture to the extreme south of the two vessels shown.