Ngāi Tahu were led in the later stages of their campaigns against the Ngāti Mamoe by the sons of the chief Tu Rakautahi. It was he who in the early years of the 18th century fixed the headquarters of the tribe at Kaiapoi (near present-day Kaiapoi), choosing the site mainly for its good defensive position on a promontory of dry land almost entirely surrounded by swamps. There he built a pā that became famous throughout the South Island for its strength and size, and the wealth of its people. The timber for the construction of the pa came from the forests from Woodend to Rangiora. ‘"The fortifications consisted of earthworks surrounded by strong palisades. The defences on the land side were strengthened by a broad ditch which extended across the entire front of the pa. Behind the wall of earth was a double row of strong palisades."’. The posts of this palisade were as thick as the mainmast of a ship.