The construction of Port Grosvenor was initiated by Captain Sidney Turner, who in 1867, with his father-in-law Walter Compton, had bought 600 acres (2.4 km2) of undeveloped Crown Land on the Natal South Coast between Umkomaas and the present village of Clansthal.
Turner and a friend, Lieut Beddoes, of the Durban Volunteer Artillery, had set off for Port St Johns in the vessel Adonis, had proceeded to the wreck and commenced blasting the rocks with dynamite.
As port captain and harbourmaster, Turner collected customs dues and managed the harbour and pilotage.
Turner was obliged by his financial circumstances to resign himself to this situation as he, by 1884, had a family of seven children and a wife to support.
The Cape Government, despite having no jurisdiction in the area, later declared Turner's concession illegal under tribal law, and he forfeited the land, his home and his position.