Rubh' an Dùnain's fort was vital to the survival of the seafaring inhabitants - protecting a safe anchorage and later guarding one of the country's unique harbours.
Using sophisticated engineering they created a long canal leading to the inland loch, with berthing slips along the way, and then lochside quays where galleys could tie up in perfect safety. Archaeologists also talk of a shipbuilding yard and the construction of galleys (birlinn in Gaelic).
It was a huge undertaking carried out over time - driven by the need for a safe haven in an otherwise harsh and forbidding shore. The 2018 BBC series, Scotland from the Sky, illustrates graphically just how extensive and complex this engineering structure was.
The control of the sea was paramount to a maritime nation and sophisticated war galleys plied the Atlantic coast and engaged in major naval battles.
Rubh an Dùnain grew into a bustling port and the new home and base of a Viking leader called Asgall who landed with his fleet after losing a row about who should run Dublin. The MacAskills had arrived.
With their superb view of the sea from a renovated fort they became MacLeod's sentries - policing the seas against pirates harrying rich merchantmen laden with luxury goods and particularly fine French wine for the tables of the nobility of the islands at the time. When the heyday of piracy ebbed the sentries defended the southern border of MacLeod country.
Rubh' an Dùnain then became a disputed land - a border zone between the MacLeods and the MacDonalds who had lost their territories in the south of the island.
However the MacAskills held their grip on the headland. Their loyalty to the MacLeods was important to them and they vigorously and successfully supported the MacLeods against all of their common enemies.
Rubh' an Dùnain was their home and they were determined to keep it that way. But after 700 years it was abandoned. Read on.