The HMAS J4 is one of Australia's few diveable submarine wrecks, sitting upright on the seabed in Victoria's deeper coastal waters at 26 to 27 metres. The hull is well encrusted with kelp and seaweed, giving it a distinctly austere, overgrown character. Visibility ranges from 5 to 15 metres depending on conditions, and strong currents are a consistent feature here, demanding solid buoyancy control and careful dive planning. Surge compounds the challenge near the wreck itself, and entanglement risks from growth and structure mean penetration attempts are not appropriate. This is a boat-access site best suited to experienced wreck divers comfortable in variable, demanding conditions.

The HMAS J1 sits on the seabed off Victoria as one of Australia's few diveable submarine wrecks, resting at 35 to 36 metres in deep diving territory. The hull is colonised by yellow zoanthid corals and attracts various fish, but the wreck demands respect before you descend. Strong currents run across the site, and the overhead environment inside creates genuine entanglement and navigation risks. Visibility runs 10 to 15 metres, which is workable, but cold water and depth mean your bottom time is short and decompression planning is non-negotiable. Boat charter with a guided tour is the sensible way to approach this one.

The Rotomahana wreck sits in 30 to 40 metres off Victoria, placing it firmly in deep diving territory and demanding proper technical preparation before you descend. Strong currents run across the site, so timing your dive around slack water is non-negotiable. Visibility ranges from 10 to 30 metres, and on a clear day the wreck structure and adjacent wall come into sharp relief. Sponges colonise the hull extensively, while sea urchins and starfish work the surrounding substrate. Large schools of fish congregate around the structure. Cold water and real decompression considerations mean this is a site that rewards experience and punishes complacency.

The HMAS J5 is one of Victoria's few diveable submarine wrecks, sitting upright on the sand at 34 to 36 metres. The confined spaces and overhead environment demand solid buoyancy control and a technical mindset before you descend. Visibility runs 5 to 10 metres, and moderate current can push through the site, so plan your entry accordingly. The hull is colonised by yellow zoanthids, which provide striking colour contrast against the steel. Seals occasionally visit, adding an unpredictable element to the dive. Nitrogen narcosis is a real consideration at this depth, and decompression obligations can accumulate quickly if you push your bottom time.

The SS Coogee sits in deep diving territory at 32 to 35 metres, making this a shore-entry wreck dive best suited to beginners who have already completed some deeper dives with a guide or instructor. Visibility can reach 15 metres, though conditions vary. The wreck itself hosts a colourful mix of marine life including yellow zoanthids, sponges, cuttlefish, catsharks, and the striking blue devilfish. Old wives, butterfly perch, large-toothed beardy, and crayfish are also regularly spotted around the structure. Be aware that currents here can be extreme, and cold water, surge, and boat traffic all require careful attention. Dive with an experienced operator and plan your bottom time conservatively.

Dragon's Lair is a boat-access reef dive off Victoria that earns its advanced rating through moderate currents and visibility that typically runs 5 to 10 metres. Working depths of 12 to 18 metres give you a reasonable bottom time, but the current demands solid buoyancy control and a good pre-dive briefing on conditions. The reef supports a range of local species, and the slightly challenging visibility adds a searching quality to the dive that rewards patient, methodical divers. Time your descent to work with the current rather than against it, and you'll get far more out of the site.

The HMAS J2 is a decommissioned Royal Australian Navy submarine sitting upright on the seafloor off Victoria at 37 to 39 metres, making this firmly deep diving territory. The wreck is largely intact, and the combination of confined spaces, potential low visibility down to 1 metre, cold water, and overhead environments demands solid buoyancy control and prior wreck experience. Visibility can reach 10 metres on a good day, but plan for less. Wobbegong sharks rest against the hull, blue devilfish tuck into crevices, and crayfish shelter beneath overhangs. Schools of fish work the water column above, while benthic invertebrates colonise most exposed surfaces. Mild current is typical, though conditions can strengthen.

Barwon Bluff Marine Sanctuary combines reef, kelp forest, and wreck diving in shallow waters ranging from 1 to 10 metres, making it an accessible shore dive with genuine variety packed into a compact site. Visibility is highly variable and can be as low as 1 metre, so conditions demand careful timing and solid buoyancy control. Surge and strong currents are real factors here, and breaking waves at entry require a confident shore entry technique. Within those conditions, you'll find various reef species working through kelp-covered structure. This site rewards patience and preparation rather than brute experience.