Though not one of the earliest spots to be defended in Jamaica under British rule, =Rock Fort=, at Harbour Head (not to be confounded with Rocky Fort on the Palisadoes), which commands the approach to Kingston from the east, or windward as it was commonly called in the days of sailing-ships, came into importance before the close of the seventeenth century. It was first fortified as a protection against the threatened French invasion from San Domingo, under Du Casse in 1694; and enlarged and strengthened from time to time. It was manned in 1865, when it was feared that the rising in St. Thomas would spread to Kingston. Near Rock Fort is the site of a =Naval Watering Place=, established by Admiral Vernon in 1739–42, where Rodney later added a conduit, still to be seen, for the conveyance of fresh water from the spring to the shore. Sir James Castile, a native of Barcelona but a naturalised Englishman, who had come to Jamaica as agent for the Assiento Company of Spain, which had the exclusive right to import slaves and other objects from Africa to the Spanish West Indies, and to which was joined the Royal African Company of England, received his letters of naturalisation in March, 1684–85; and in the July following he acquired land in Port Royal, where he established offices for his company, which he could not have done had he been an alien. In 1690 he purchased 300 acres of land in the old parish of Port Royal (now St. Andrew), near Harbour Head, and in the following year he acquired one hundred more in St. Andrew near by. In September 1693 letters patent were issued by the governor, Sir William Beeston, authorising Castile “to enclose his dwelling house at Three Rivers in the Parish of St. Andrews, with imbattled walls for the security and defence of his said house and plantation and negroes and the parts adjacent, against their Majesty’s Enemys”; and thus arose Fort Castile, about a mile and a quarter beyond Rock Fort. In the June following, under fear of French invasion, with the defences of Port Royal ruined by the recent earthquake, Colonel Lawes “drew lines and secured a narrow pass to the eastward of Kingston,” and this became Rock Port, and Du Casse was led to make his attack to the west of St. Jago de la Vega at Carlisle Bay. Sir James assisted not only at Rock Fort, but also at his own dwelling; “having garrisoned and provided his house, which was well walled and guarded for a defence, they built a regular fort on the parade.” In 1702 Castile petitioned the House of Assembly in respect to the great charge he had been put to in building Fort Castile, and the House voted him £500 in compensation. He died in 1709, and in 1711 his widow petitioned for consideration in view of the fact that for five years the fort was occupied by her Majesty’s forces, “during which time it ran greatly to ruin.”