Traces of all historic periods could be found in the area of the town of Kaštela; cavemen have hunted here (Mujina Cave on the western slopes with artifacts dating 45 000 years BC).
There are many Illyrian stone heaps scattered over the Kozjak Mountain.
During the Greek and Roman rule these parts experienced their economic and cultural prosperity. Remains of many antic villas and the Siculi settlement at Resnik are the proofs of that.
Croatians migrated to the gentle slopes of Kozjak in the 7th century and formed their first settlements. Old Croatian churches are the silent witnesses of that time.
Aristocrats and clergymen from Trogir and Split built their castles on these rocky shores. The Venetian authorities approved of that to protect crops and peasants. These fortified mansions– castles appeared as fortresses on their land sides with keeps, moats, loopholes and drawbridges. Their sides facing the sea were built as Renaissance villas with wide windows and balconies. Inhabitants of the old settlements on the slopes of Kozjak sought refuge and security by building new fortified settlements around them.
Agriculture and growing of olives and grapes were the basis of economy and the foundation of economic might of these parts. Big churches with bell towers (decorated by most famous artists of that time), golden and silver gifts in church treasuries and folk costumes noted for their golden decorations and golden embroidery witness about that might.