The Ships' Graveyard sits in around 30 m of Bass Strait water roughly 5 km off Barwon Heads, where decommissioned vessels have been scuttled to create an artificial reef. The site is a wreck-diver's playground — multiple hulls within a small radius, all encrusted with sponges, ascidians, gorgonians and home to blue devils, banjo sharks, big schools of bullseyes, leatherjackets and the occasional fur seal. At 30 m it's strictly an advanced dive with short bottom times. Boat access only, run by charter operators out of Queenscliff or Geelong. Best in light north-east winds, swell under 1.5 m and tide near slack to keep current down. Use the live 7-day wind and swell forecast on this page to pick a flat day. Advanced and deep-trained divers only — depth, current, and 5 km offshore means you need a proper boat and proper plan.
How far you can see underwater — measured in metres. 10m+ is great, 5–10m is workable, under 3m is murk. Driven by wind, swell, and recent rain.
Long-period waves rolling in from the open ocean. Direction matters more than height — a S swell hits Portsea hard, but an E swell rolls past. Period over 12 s = real ocean punch.
Offshore (N or NE) flattens the surface and clears the water. Onshore (SE through SW) chops it up and stirs sand. Calm or light offshore is the magic combo.
This site faces the open ocean. The exposure caption above shows which directions slam in. Anything from the opposite side gets blocked — that's the safest window.
Slack water — the 30 minutes either side of high or low — is calmest and clearest. Mid-tide brings the most flow. Plan to be down at slack, up before the run picks up.
Bass Strait sits 14–16 °C autumn–winter, 17–19 °C summer. Below 16° a 7 mm hooded keeps you warm for 60 min+. Drysuit if you're going long.