Along with the physical growth of the city came an increase in the population. The population of the city was estimated to be approximately 20,000 in 1675 rising to about 25,000 by 1700. Estimates for the population in the mid 1700s vary from 40,000 to 56,000. For the late 1700s, estimates vary from 52,000 to 80,000 (Burke, 2007c).
Descriptions of eighteenth century Cork indicate that there was widespread prosperity with the city’s population largely at work and its port developing into the second most prominent in the country based mainly on the provisions trade:
“The unrivalled ability of Cork Harbour to shelter the biggest fleets assembled during the American War of Independence and, later, during the Napoleonic Wars was a major factor in the expansion of the provisions trade in Cork. Salted beef, pork and butter were exported to the West Indies and were used to provision the British navy. Cork Butter Market (7), with its strict and rigorously enforced system of quality control, was world famous and became the largest butter market in the world for its time” (Burke, 2007d).
Significantly, the rise in exports during this time paralleled the physical growth of the city. Some of the business of the port had moved beyond the city walls eastwards. The north and south channels of the River Lee currently converge to the east of Custom House Quay, but in the eighteenth century the south channel was separated at this point from the north channel by a large marsh. Surrounded by swamp and river, Cork’s growth depended on reclamation. The first real attempts to improve the upper harbour for shipping were made in the 1760s when work began on the construction of a ‘navigation’ or ‘tracking’ wall. The Navigation Wall (8) as it became known was intended to regularise the current in the north channel of the river by directing the flow of the south channel into it at a point nearer to the city quays, and to enable ships facing contrary winds to be pulled by horses closer the city. As late as 1800, a gap was left in the wall at its western extremity to enable smaller vessels access to the original course at the south channel. From 1820 onwards a dredging programme was pursued to support the development of port trade with the material being deposited behind the Navigation Wall resulting in the completion of the Marina promenade in 1870.  The area back filled behind the wall is the site of the present day South Docks.
Figure 1: Connor’s Map of 1774 showing the development of the Navigation Wall
Source: Cork City Council Libraries, 2007.
Figure 2: The Marina
In 1784 the Custom House (10) and the offices of the Harbour Commissioners relocated from its original location between the medieval city and St. Patrick’s Street (present day Crawford Art Gallery), eastwards to the confluence of the north and south channels. This new location was prompted by a conscious decision to control shipping access to the north and south channels as it marked the precise point at which an opening had been left in the Navigation Wall. It is likely that the eastern tip of the island was first reclaimed and held by cut limestone quaysides on all sides allowing the development of an advantageously accessibly three-sided quayside complex. At the start of the nineteenth century the Butter Weighhouse Act appointed the city’s Mayor, Sheriffs and twenty-one merchants to a powerful new body, The Cork Harbour Commissioners, “a body that has joined the destiny of the city to the destiny of the sea for nearly two centuries” (McCarthy, 2005). The Bonded Warehouses (11) were completed in 1818 as part of the Custom House Quays complex, and the entire complex is included in the City Council’s Record of Protected Structures.
Figure 3: The Custom House
Figure 4: Bonded Warehouses
 The Gaelic Poet and Scholar Donnacha O’Floinn suggested to the Improvements Committee of Cork Corporation that the walk be named Sli na hAbhann which means the “way of the river”. O’Floinn’s proposal was defeated. The matter came before the Improvements Committee again in 1872. This time O’Floinn suggested that the promenade be named ‘The Marina’ (9). He pointed out that ‘The Marina’ was the name given to recently reclaimed land near Palermo in Sicily. In July 1872, Cork Corporation formally adopted “The Marina” as the name of the new promenade.
 According to Dr. Colin Rynne of U.C.C. (Rynne, 2006) the Customs House Quays are, along with Haulbowline Island, one of the two most important Georgian dock complexes outside Dublin and one of three surviving Georgian dock complexes in Ireland. Abraham Hargreaves designed the Harbour Commissioners offices consisting of the street fronting offices and the former Revenue Offices to the rear.
 The Bonded Warehouses complex is a rare example of an early form of fire-proofing using vaulting and stone flag forms. This was essential given the high value nature of the stored goods, namely spirits and tobacco. Externally the Bonded Warehouses display wooden framed and slate awnings, original hoist mechanisms and distinctive fireproof stairwell towers and warehouses are still used for their original purpose.