Flank margin caves (FMC) have been predominantly described on carbonate islands such as in the Bahamas or the Marianas, using the Island Karst Model. This model has been used to explain karst development on young carbonate islands with poorly cemented eolianites, which differ substantially from continental karst, formed in well cemented limestones. Karst on continental margins especially the southern Australian coast, are not in well cemented telogenic rocks but in highly porous, highly permeable marine and eolian calcarenites. The gradual uplift over the past 50 Ma of the southern edge of the continent has resulted in Flank Margin Caves which formed in a coastal setting, being positioned significantly further inland and reflect the neotectonics of the Southern Australian passive continental margin rather than solely the Pleistocene glacio/eustatic sealevel fluctuations. The inter-relationship of tectonic setting, the distinctive characteristics of FMC and the speleogenesis of coastal karst assists in the understanding of the karst landscape evolution of significant karst areas of southern Australia.