The three concrete observation posts built into the top of Dripstone Cliffs in Casuarina Coastal Reserve Darwin, were part of a number of observation posts constructed around Darwin from 1939. The posts formed part of a coastal defence strategy developed to help defend Darwin, in anticipation of a sea and land based invasion by the Japanese during WWII. The observation posts on Dripstone Cliffs are located in an easily accessible and highly visible position.
A number of observation posts of various designs were built between Shoal Bay and East Point from 1939 to 1941. Three observation posts located within the Dripstone cliff top within Casuarina Coastal Reserve were constructed to provide a clear view of the sea and the length of Casuarina beach. Two observation posts are located in a south-facing cliff wall and offer views towards Rapid Creek and Nightcliff Jetty. The third post is small and highly exposed. It has views north and south along Casuarina beach and one wall is inscribed with the words “SGT M.Pomeroy 27 Batt”.