Castillo de la Duquesa Monument · Manilva, Costa del Sol Occidental, Málaga Fortification built in 1767, during the reign of Charles III, on La Duquesa beach, in Manilva. In its surroundings remains have been found of a Roman villa with baths, a necropolis and a 2nd-century AD fish-salting factory. 1767 Photo: ZC.Marbella (CC BY-SA 4.0) What to see and do in Manilva