Mill Arm is named after a former sawmill. The Mill Arm is the most used anchorage in Greville Harbour and various parts of it give shelter from all wind directions. This is an extremely attractive area and is surrounded by native bush. The head of the arm is shallow and boats should not attempt to use the last 400 m of the arm.
The first mill in this bay was established during the 1870-1880s.
The area was also said to be a sanctuary for seagulls.1