The Princess Margaret Rose Cave is a limestone cave located in Lower Glenelg National Park in Victoria, Australia. The cave features actively growing stalactites, stalagmites and helictites. The cave was formed in poorly consolidated Tertiary limestone laid down in a shallow sea in the Oligocene and early Miocene geological epochs, between about 35 and 15 million years ago. Princess Margaret Rose Cave in South Western Victoria, is about 2 km from South Australian border and is also accessible by boat along the Glenelg River about 11 miles upstream from the small seaside settlement of Nelson.