The Down Survey maps of 1655 to 1659, a vast Commonwealth-era project that set out to document landownership across Ireland, show a double row of houses with a tower house rising between them, the whole settlement strung along the harbour in much the same shape the village retains today. A contemporary written account, the terrier accompanying the Kilmoe parish map, described the place with some enthusiasm: 'there is in this parish a very good Harbour called Crookhaven having a Fort Commandinge the Entrance in which Shipps may lye securely, Theres likewise a Towne neere to this Harbour called Crookehaven in which Stands a Castle and many Cabbins.' The castle has never been precisely located, and no local tradition appears to have preserved its memory.

The settlement itself was largely a planted one. Sir Thomas Roper established a fishery station at Crookhaven in the early 1600s and, according to historian Colin Breen, hundreds of families were settled there as part of that enterprise. By 1622 Roper had also stationed a garrison of soldiers in the town, and a fortification associated with that garrison appears on the Down Survey Barony map near the village. The harbour, which the terrier called 'very good,' is further confirmed by the first edition Ordnance Survey six-inch map, which marks three quays and a Fish Pond to the north of the village. The church and graveyard at the western end of Crookhaven, still present today, most likely occupy the site of an earlier ecclesiastical foundation. What is striking is how much the 17th-century settlement plan, a garrison town built around a working harbour and a castle that has since vanished without trace, persists in the bones of the modern village, even as the castle itself remains unlocated and the fort that once commanded the harbour entrance is equally elusive.