During the 11th and 12th centuries both invaders and defenders built more than fifty castles during a complex period of conflict, effectively to consolidate the line. The southernmost was Laugharne; others included Wiston, Camrose, Narberth, and Roch. These are often referred to as "frontier castles" but they were in fact set back a considerable distance from the frontier itself. In the heart of the Normanised colony, the two great fortresses were at Pembroke and Haverfordwest. There were other fortresses within the colony as well, including Manorbier, Carew and Tenby.