HMAS Koompartoo was a Sydney Ferries Limited K-class ferry later converted to an Royal Australian Navy boom defence vessel. Koompartoo and her sister ferry, Kuttabul, commenced ferry service in 1922. The highest capacity ferries to ever run on Sydney Harbour, they were designed and built for the short heavy-lift run on the Circular Quay to Milsons Point across to Sydney's North Shore prior to the 1932 opening of the Sydney Harbour Bridge.