The first HMAS Warrnambool was a 1000 ton, 57 metre minesweeper launched in 1941. She was in Darwin when it was bombed but escaped with only slight damage, later being used for troop transport, convoy escort and submarine detection. After the war the ship was used for mine clearing around New Guinea and the Great Barrier Reef, It was here, near Cockburn Reef in September 1949 that she hit a mine and sank, 4 of the crew were killed and 29 injured.
The second HMAS Warrnambool was a Fremantle class patrol boat of 220 tons, built in Australia and launched in 1980. Much of her work was patrolling northern waters for illegal fishing and oil rig surveillance in Bass Strait. This vessel visited Warrnambool in 2001 and was decommissioned in 2005.
Look out beyond Lake Pertobe to Lady Bay, where over twenty ships were wrecked or stranded. Back in the late 1800s Warrnambool was a very busy seaport, however the bay was exposed to weather from the west and a long double reef which extends from the western end of the bay. Three islands at the western end provided little shelter for ships coming into the harbour. The Breakwater was built in the 1880s from 32 ton concrete blocks, fabricated in Pertobe Rd near the present army depot site and transported along a purpose built railway track. The construction began on top of one of the islands and extended in an easterly direction, for 900 feet, however it proved inadequate and later an extension was added. Over time the breakwater has aggravated the siltation of the bay. The port was officially closed in 1942, though it is still home to a small fleet of fishing boats and recreational users.