Some of Nelson’s most expensive real estate facing Tasman Bay sits on a prehistoric landslide known as the Tāhunanui Slump. The hillside above Rocks Road from Magazine Point (left) to Tāhunanui Beach (right) is a landslide that started moving a few thousand years ago. The edges of the landslide are marked by the green line, and it is divided into active (currently moving) and inactive (ceased moving) portions. The boundary between these portions is indicated by a white line. The landslide tends to move most during heavy rainfall, or ground shaking caused by earthquakes. Building restrictions mean that any further development on the active part of the slump is unlikely, as parts of it are still moving, albeit very slowly.