SMS Cormoran II & Tokai Maru – Apra Harbor
Site Overview
The SMS Cormoran II and Tokai Maru represent one of the most extraordinary dive sites in the world, where two shipwrecks from two different world wars lie touching each other on the seabed of Apra Harbor. The German SMS Cormoran II, a WWI commerce raider scuttled by her crew in 1917, rests at approximately 35 metres with her massive propeller and coral-encrusted decks creating an artificial reef of remarkable biodiversity. Lying directly atop and alongside the Cormoran is the Tokai Maru, a Japanese freighter sunk during the 1943 Allied bombing of Guam, sitting shallower at 15 to 20 metres. This unique arrangement means a diver can literally touch ships from both world wars in a single dive, an experience available nowhere else on Earth. The wrecks have become thriving ecosystems, covered in soft corals, sponges, and gorgonians, attracting lionfish, batfish, moray eels, and schools of jacks. The historical significance combined with the rich marine life and dramatic wreck structures make this a bucket-list dive for any serious wreck diving enthusiast. The site is accessible by boat from Apra Harbor operators and is typically dived as a multi-level profile starting shallow on the Tokai Maru and descending to the Cormoran for qualified divers.
Dive Briefing
"Descend from the mooring buoy onto the shallow deck of the Tokai Maru at approximately 15 to 20 metres. This Japanese freighter was sunk during World War II and sits upright with accessible cargo holds and deck structures covered in decades of coral growth. Work your way along the starboard side to the point where the Tokai Maru touches the deeper SMS Cormoran II. The German WWI raider sits at approximately 35 metres, so monitor your depth and bottom time carefully. The Cormoran features a massive bronze propeller, intact deck guns, and crew quarters encrusted in colourful corals. Lionfish are abundant on both wrecks, along with batfish, moray eels, and schooling jacks. Maintain good buoyancy throughout to avoid disturbing the fragile coral encrustation. The standard exit is a slow ascent along the mooring line with a safety stop at 5 metres. Total dive time typically runs 40 to 50 minutes depending on depth profile. Currents are generally mild within the harbor but can strengthen during tidal changes."
Signature Marine Life
Lionfish
Pterois volitans
Best: January, February, March
Batfish
Platax orbicularis
Best: January, February, March
Moray Eel
Gymnothorax sp.
Best: January, February, March
Barracuda
Sphyraena sp.
Best: November, December, January
Jack
Caranx sp.
Best: November, December, January
Coral Grouper
Cephalopholis miniata
Best: January, February, March
Safety & Hazards
- Depth reaching 35 metres requires careful air management
- Wreck penetration hazards including silt-out and entanglement
- Marine stingers including lionfish spines
- Boat traffic in working harbor
- Strong currents during tidal changes
- Corroded metal edges inside wrecks
Traveler Notes
Who is this for?
This site is designed for Advanced Open Water certified divers and wreck diving enthusiasts seeking one of the most historically significant underwater experiences in the Pacific. The depth reaching 35 metres on the Cormoran requires good air management and experience with multi-level diving profiles. Wreck penetration should only be attempted by divers with appropriate Wreck Diver specialty certification. The site is equally rewarding for divers who stay within recreational limits on the shallower Tokai Maru, which offers excellent photography and marine life observation at comfortable depths. History buffs will find the dual-wreck concept profoundly moving.
Quick Stats
Dive Logistics
- Coral Reef Ocean World
- Guam Dive Center
- Aqua Sport Guam
- Pacific Divers Guam
Photography Info
Best for: wide_angle, macro