under the control of the Royal Navy, although the naval dockyard on Haulbowline Island was handed over to the Irish Free State in 1923. Although the Royal Navy appreciated the location of Cork Harbour, particularly for submarines, which had a significantly shorter range in the 1920s, maintenance of the fortifications became an issue after Ireland became independent. The political uncertainty over the future of the treaty ports meant that the British government was not inclined to invest in their upgrade. Also, at the time of their construction, nobody had considered the possibility of air attack and as they were unable to expand, there was no possibility of adding adequate air cover. Finally, if the Irish Free State was hostile during any conflict, the treaty ports would have to be supplied by sea rather than land, wasting resources. In March 1938, the British government announced that the treaty ports would be handed over unconditionally, and on 11 July 1938, the defences at Cork Harbour were handed over to the Irish military authorities at a ceremony attended by Taoiseach Éamon de Valera. Since being handed over to the Irish military, most of the military installations have ceased to be used for military purposes. Fort Carlisle was renamed Fort Davis and is used by the Defence Forces for training - but is in a somewhat neglected state. Fort Camden became officially known as Fort Meagher and while no longer in military use, has been subject to renovation by local volunteers and enthusiasts, and can be visited by the public on certain days. The fort was officially renamed as of 11 July 2013 as Camden Fort Meagher, to account for both its British military and Irish military history. Locally, the two forts are sometimes known as "Camden" and "Carlisle", rather than their official titles. Fort Westmoreland became Fort Mitchell Spike Island prison, and has since ceased use for military or prison purposes. "Spike" was gifted to Cork County Council by the State and has been renovated as a tourist attraction by council workers and volunteers under the supervision of archaeologists. The fortifications on Haulbowline Island however have been maintained, and are now the headquarters of the Irish Naval Service. Industry Cork Harbour is one of the most important industrial areas in Ireland. While several traditional industries such as shipbuilding at Verolme Dockyards, steel-making on Haulbowline Island and fertiliser manufacturing at IFI (Irish Fertiliser Industries)