At about the end of the sixteenth century the central tower apparently gave way, carrying with it the north wall. Afterwards large portions of the ruins were taken away for building purposes, and nothing was done to preserve them until 1826. Since then it has been tended with scrupulous care, an interesting feature being the cutting out of the ground-plan in the turf. The principal portions extant, partly Norman and partly Early Scottish, are the east and west gables, the greater part of the south wall of the nave and the west wall of the south transept.