Aboriginal skeletal remains and artefacts had been eroding out from a dune north of Blanchetown, along the River Murray for many years. Once exposed, remains were lost either to souvenir hunters or to destruction from the natural elements. In 1969, South Australian Museum archaeologist Graeme Pretty implemented a rigorous excavation program to prevent further loss. The excavation was undertaken at a time when very little archaeological work was being carried out in Australia. Roonka still stands as the largest investigation ever undertaken on a burial site in this country. This is the story of that excavation and how it has revealed the mysteries of the Ngaiawang.