Coron wrecks

What happened at Coron on September 24, 1944?

In early September 1944, raids by American carriers made the big anchorages of the Philippines untenable, and Japanese ships sought refuge in Coron Bay, between Busuanga and Coron Island, away from the shipping lanes. On September 21, Vice Admiral Mikawa Gunichi obtained the transfer of the supply ships from Manila Bay to Coron; that same day, the Irako weathered the Task Force 38 raid in Manila and took on survivors from the destroyer Satsuki. On the 22nd at 3 a.m., a convoy left Manila for Coron with the Irako, the Taiei Maru and the Olympia Maru; the Akitsushima arrived on the 23rd.

On September 24 at 9 a.m., aircraft from the carriers Intrepid, Cabot and Lexington, launched more than 340 miles from their ships, fell on eleven vessels at anchor. In a single morning they sank the Akitsushima; the Irako, scuttled after its damage; the Kogyo Maru and its 39 dead; the Olympia Maru, hit on the fourth pass of a squadron of ten bombers, with 19 dead; the Taiei Maru, the Kyokuzan Maru, the Terukaze Maru and the Lusong gunboat. The Okikawa Maru, a burning tanker, stayed afloat for a few more weeks before a direct hit on the bow. In the 1970s, salvagers raised engines and propeller shafts from some hulls; the rest stayed in place, and the bay is now a national historical site. In February 2026, six models of the wrecks, surveyed by photogrammetry and 3D printed, entered the National Museum of the Philippines.

What are the Coron wrecks, one by one?

The Okikawa Maru, a 160 to 168 m tanker, is the biggest wreck in the bay: upright on the bottom at 26 m, its deck between 10 and 16 m, its bow almost torn off, dense coral along its whole length, and a penetration through the propeller shaft tunnel to the engine room. The Akitsushima, a 115 to 118 m seaplane tender, is the only true warship: lying on its port side between 22 and 36 m in the channel between Lajo and Manglet, it has its 35-ton crane resting on the sand, its machine guns, its radio mast, a huge impact hole, and three decks to explore down to the four engines for trained divers. The Irako, a 145 m refrigerated supply ship, is the deep wreck, from 28 to 43 m, almost upright, its bridge hit head-on; the engine room, galley and holds full of provisions can be visited with a light, and guides call it DDD, deep, dark and dangerous. The Kogyo Maru, a 130 to 135 m freighter lying on its starboard side between 22 and 34 m, was carrying what was needed to build airstrips: a bulldozer, a tractor and collapsed bags of cement wait in its six holds. The Olympia Maru, a 122 m freighter sitting upright between 18 and 32 m near Tangat, is the easiest of the big wrecks, with open holds. The Morazan Maru, a British passenger-cargo ship from 1907 captured by the Japanese, 92 m long and lying on its starboard side between 12 and 26 m, can be swum through from bow to stern, past two boilers. Outside the bay, northeast of Busuanga, the Kyokuzan Maru, 180 m between 20 and 28 m, is almost intact, with its pottery and truck parts, and an asbestos-covered bottom you don't stir up. The two gunboats complete the picture: the East Tangat Gunboat, a 35 m submarine chaser between 3 and 19 m, and the Lusong Gunboat, 30 m long, whose stern breaks the surface at low tide, reachable by snorkeling.

What is it like to dive the freshwater Barracuda Lake?

On Coron Island, 30 m from the sea behind a limestone wall, Barracuda Lake is a karst lake that dive centers add to a wreck day. The water is fresh and 28°C down to 14 m; there, a sharp thermocline and halocline take you into salt water at 38°C, which makes a wetsuit pointless and the feeling strange. The bottom, around 32 to 35 m, is a gelatinous brown silt colored by tannins; a 30 m long cave opens at 33 m, one diver at a time. There is almost nothing alive to see, a big resident barracuda on good days, and that's the reason to go: you dive it for the walls, the light and the temperature. The island has been ancestral domain of the Tagbanwa since 1998; entry costs PHP 200 to 300 depending on the dive center, and at the surface you swim with a vest.

How do you get inside the holds of the Coron wrecks?

The Coron wrecks are learned in order: the Olympia or the Okikawa first, for buoyancy and bearings, then the Morazan, the Kogyo, the Akitsushima and the Irako last. Dive centers sell the wreck course on site, one day with SSI, two with PADI, and take only divers who hold it into the engine rooms. A powerful light is essential in the Irako and useful everywhere; the photo subjects are the Akitsushima's crane under its batfish and barracuda, the Okikawa's corals between 10 and 16 m, and the light shafts in the engine rooms of the Kogyo and the Morazan. Dive before high tide for visibility, fin well clear of the plates so you don't lift the silt, and touch nothing: these are war graves, and some still hold their munitions.