Begin excellent sailors, since the 13th to century the inhabitants of Omiš had been controlling the navigation of ships thus making problems to developed communities on the eastern Adriatic coast as well as to Venice that had economic interests outside the Otrant. Therefore in the old mediaeval books on ports, harbours and navigation, Omiš(Almissa, Dalmissa, Dalmesa) is not recorded as a good port but as a dangerous shelter for pirates such as Saracens on the Mediterranean or the Tatars in the Black Sea. The Statute of Dubrovnik strictly forbids selling of boats to inhabitants of Omiš. Attacks and plundering were directed to Venetian boats and Venetian properties in Dalmatia, as well as to boats under the flag of the Kingdom of Naples. It is very probable that at the beginning of the 14 Century a tribute for free navigation was paid to Omiš by Italian ports of Puglia and Marche.
The frontier of mediaeval Omiš together with the region of Poljice was the river Cetina than in its long course had shaped many a wonder of nature. Above its canyon on the lower Cetina frontier fortresses Kunjak and Visuæ were built which defended the district of Omiš. In 1423. “castella circa Dalmissiam” are mentioned, was the fortress Starigrad (old town). In King Fridrich’s III. Chart from1454. it is mentioned as “castrum Stary”, and in that from the same year of Alonso V. King of Naples and Argon it is mentioned as “civitate Antiqua”. The fortress is situated at the top of the mountain over Omiš – a site of strategic importance with a board view on all movements across the middle Poljica as well as over the navigation in the sea channel between Split and Makarska.
The name Starigrad is a Croatian name for “old town” because it originated on the site of the antique castellum Oneum while the “new town Omiš” developed on the coast. Under this name it is mentioned in documents in Latin and Italian as well as in cartography from the 15. to the 17. century. Later, under the influence of Italian military terminology the term Fortica(The Fortress) was used.
Throughout the 16. century (1534., 1559., 1566., 1571.-1573., 1586.) the fortress Starigrad was reinforced several times due to a growing danger of Turkish attacks. Major repair works were done during the Kandian war (1654.-1669.) By the end of the century Omiš is not anymore in Venetian – Turkish frontier area and with the spreading of free territory the strategic importance of this fortress decreases.
During the last aggression on Croatia (420 years after Turkish sieges) a group of monument lovers from Omiš, helped by school children and the young – without any modern technological devices succeeded to restore this neglected and damaged fortress.