San Francisco Maru

Divers call the San Francisco Maru the Million Dollar Wreck, an accountant's nickname for a cargo no museum could assemble: three Type 95 light tanks chocked on her foredeck, truck chassis, aerial bombs, hemispherical mines, torpedoes, artillery shells, and drums of fuel, all stowed for a garrison that never received them. Built in 1919, she was an aging freighter by the time Hailstone's second-day strikes set her afire in February 1944, and she went down upright into one of the deeper anchorages of the lagoon. That depth is the reason she looks the way she does — beyond the reach of salvage and most souvenir hunters, her cargo sits in parade order under a thin dusting of silt. It also defines the dive: the tanks appear out of dim blue at more than forty meters, and the seabed lies past sixty. She is the lagoon's benchmark technical wreck, and men died aboard her; she is dived as a grave.

How she sank: Bombed by US carrier aircraft on the second day of Operation Hailstone, 18 February 1944.

Condition: Remarkably intact, with cargo undisturbed; the cold arithmetic of depth has preserved her better than any ordinance could.

Penetration: Limited. Hold entries are open-topped and brief for those qualified to be at this depth at all; true interior work is for experienced technical teams only. Entering any overhead environment requires specific training — a wreck certification at minimum, technical wreck training for full penetration.

Recommended certification: Technical/trimix certification; this wreck lies below sport-diving depths

Current: Mild · Visibility: 15–30 m

Marine life: Growth thins at depth — wire corals, sponges, and patrolling trevally rather than the shallow wrecks' gardens.

Hazards: Depth, decompression obligation, and narcosis management; a dense cargo of live ordnance; low ambient light.

Chuuk lagoon monument protection; state dive permit/fee applies.

A war grave — remains have been found aboard. Nothing is touched, nothing is taken.

Removal is illegal and, given the cargo, potentially lethal.