 When the treaty of Seville was concluded between Great Britain, France and Spain in 1729, long arguments ensued between Spain and Britain as to how far north the 'undoubted right' of Britain extended from the north face of the Rock of Gibraltar.It was finally accepted that a distance of 600 "Toises", being more than two cannon shots distance between the British guns and the Spanish guns, would be considered “the neutral ground”.In either case, the United Kingdom further bases its claim upon what they consider to be established legal precedents that grant property rights over an area that is continually occupied and made sole use of, for an extended period.