This dive site is one of many on Lonsdale Wall, located just inside The Heads on the Lonsdale side of Port Philip — one of Australia's premier dive locations.

Lonsdale Wall is one side of an underwater canyon formed by the old Yarra River as it flowed out to sea through the plains, carving steep-walled edges out of soft rock sides. Between the end of the last Ice Age around 8000 BCE and around 6000 BCE, the sea-level rose to drown what was then the lower reaches of the Yarra River. Thus the canyon formed by the river near what is now The Heads, or The Rip, was flooded creating the Lonsdale Wall, North Wall and Nepean Wall areas.

Lonsdale Wall extends for one kilometre, providing many spectacular dive sites. An almost vertical drop characterises Lonsdale Wall with the wall starting as shallow as 8 m (26 ft) metres deep in places and sometimes dropping down to well over 60 m (197 ft) deep.

Lonsdale Wall

 Wall Dive |  Boat access

Lonsdale Wall | © Phil Watson

Depth: 12 m (39 ft) to 38 m (125 ft)

The Lonsdale Wall dive site is but one of the many spectacular dive sites on Lonsdale Wall. The tidal flow in and out of Port Phillip each day means this site is in high-velocity waters providing plenty of nutrients for the marine life that densely covers Lonsdale Wall. Thus this site should be dived on the short window of slack water. Dive charter boats operating out of Portsea and Queenscliff regularly schedule this dive site, or one of the other dive sites on Lonsdale Wall. Private dive boats usually head out to Lonsdale Wall from the Sorrento or Queenscliff boat ramps.

The Swim Through, by Jane Headley.

Tom Wende diving Lonsdale Wall
© Sonar Wetsuits

Lonsdale Wall has overhangs and ledges and undercuts providing sanctuary to an enormous variety of fish including the spectacular Southern Blue Devil, Leather Jackets, Dusky Morwong, Southern Hulafish, Old Wives plus Southern Rock Lobster (aka Crayfish) and Giant Australian Cuttlefish. Occasional sightings of a Port Jackson Shark snoozing under a ledge, or and if you are really lucky you may even spot a Gulf Wobbegong or Sharpnose Sevengill Shark cruising slowly along the wall. Colourful growth in the form of soft corals, sponges, hanging sea fans in bright yellow, orange and other varieties in pink and burgundy. At least four different species of Nudibranchs and Seastars can be found here if you look closely.