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Chuuk Lagoon

September 2001 and May 2003 saw us visiting Chuuk Lagoon Micronesia, to dive the historic wrecks located in and around the lagoon. We spent 7 days aboard the S.S.Thorfinn, a 58m/170ft steam powered converted Ice Class Antarctic whaler. On our September 2001 we arrived 2 weeks after the September terrorist attacks in the U.S. This saw us sharing the boat with only 6 other guests, 4 Poms and 2 Canadians; it sleeps 22 - so we were looked after very well by the 21 crew. The May 2003 visit coincided with the war in Iraq which meant not many people were travelling and we had the Thorfinn all to ourselves as we were the only guests on board.

Although the day was action packed, we never got tired. This was due to the great attention we were given by the crew. Not once did we have to lift a finger to carry any gear, tanks etc. They passed cameras, torches and equipment to us in and out of the dive boat, and up and down from the Thorfinn. All we had to do was show up on time and roll into the water.

Our guide Bettewien was great and put us at ease on the deeper dives with his quiet gentle nature.
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A Brief History of Chuuk

Chuuk Lagoon, also known as Truk Lagoon, is a large body of water located in the Federated States of Micronesia in the Pacific Ocean. It is a popular destination for scuba divers and history enthusiasts, as it is home to one of the most significant wreck diving sites in the world. In this article, we will explore the history, geography, and tourism of Chuuk Lagoon. Chuuk Lagoon has a long and complex history. The islands were first settled around 2000 BCE by Micronesian peoples, who established a thriving culture based on fishing and agriculture. The islands were then colonized by the Spanish in the 16th century, who introduced Catholicism and European trade to the region. However, Spanish rule was short-lived, and the islands were annexed by the Germans in 1899. During World War I, Japan seized control of Chuuk Lagoon from Germany and established a naval base there. The Japanese built a series of fortifications and airfields throughout the region and used Chuuk Lagoon as a major logistical center for their operations in the Pacific. However, the US forces launched a massive air and sea assault on Chuuk Lagoon in February 1944, and within a matter of days, the Japanese forces were defeated. Chuuk Lagoon is a large, shallow body of water that is surrounded by a series of islands and coral reefs. The lagoon itself is approximately 40 miles long and 25 miles wide, with an average depth of 50-60 feet. The islands that surround the lagoon are part of the Chuuk State of the Federated States of Micronesia and are home to a population of approximately 50,000 people. The islands of Chuuk Lagoon are known for their lush tropical vegetation, white sand beaches, and crystal clear waters. The lagoon is also home to a diverse array of marine life, including tropical fish, sea turtles, and sharks. The coral reefs that surround the islands are home to a variety of hard and soft corals, and the underwater landscape is dotted with shipwrecks and other remnants of the region's history. Chuuk Lagoon is a popular destination for scuba divers and history enthusiasts from around the world. The wreck diving in Chuuk Lagoon is considered to be some of the best in the world, with over 60 wrecks scattered throughout the lagoon. The wrecks include Japanese warships, cargo vessels, and even aircraft, many of which are still intact and provide a fascinating glimpse into the region's history. In addition to wreck diving, Chuuk Lagoon is also known for its beautiful beaches, lush rainforests, and vibrant cultural heritage. Visitors can explore the islands on foot or by boat, taking in the sights and sounds of the local villages and markets. The region is also home to several historical sites, including Japanese bunkers, airfields, and other relics of the region's past. Chuuk Lagoon is also a popular destination for eco-tourism, with several conservation projects aimed at preserving the region's delicate ecosystem. Visitors can participate in activities such as sea turtle monitoring, coral reef restoration, and beach clean-up projects, helping to protect the natural beauty of the region for future generations.


Overview of Operation Hailstone

During World War II, Operation Hailstone emerged as a critical military campaign, marked by an intense aerial assault on Chuuk Lagoon, a major Japanese naval base located in the Caroline Islands of the Pacific. Spanning from February 17 to 18, 1944, this operation proved to be one of the most significant American offensives in the Pacific theater. With its strategic implications and the remarkable devastation inflicted upon the Japanese forces, Operation Hailstone played a pivotal role in turning the tide of the war. This article delves into the historical context, objectives, execution, and consequences of Operation Hailstone, shedding light on its enduring impact. Following the attack on Pearl Harbor in December 1941, the Japanese Empire expanded its control over the Pacific, establishing Chuuk Lagoon as a key naval stronghold. The lagoon's natural geography provided a well-protected harbor, making it an ideal base for the Japanese Imperial Navy. Recognizing the significance of Chuuk Lagoon, the United States sought to neutralize this threat and gain a strategic advantage in the Pacific. The primary objectives of Operation Hailstone were to weaken the Japanese naval forces in the region, disrupt their supply lines, and diminish their ability to project power. By attacking Chuuk Lagoon, the American forces aimed to neutralize the major Japanese fleet anchorage, destroy naval vessels, aircraft, and infrastructure, and demoralize the enemy troops stationed there. Operation Hailstone commenced on February 17, 1944, with a massive two-day assault involving carriers, battleships, cruisers, destroyers, and carrier-based aircraft. The United States Fifth Fleet, under the command of Admiral Marc A. Mitscher, spearheaded the operation. American aircraft carriers, including the USS Enterprise, USS Lexington, USS Yorktown, and USS Bunker Hill, launched waves of airstrikes against Japanese targets in and around Chuuk Lagoon. The assault comprised coordinated attacks on the naval vessels, airfields, and shore facilities. Waves of fighter planes and bombers strafed and dropped bombs on Japanese warships, supply ships, submarines, and aircraft stationed in the lagoon. The relentless barrage unleashed destruction upon the enemy forces, sinking around 60 Japanese vessels, including four cruisers, two destroyers, and 270 aircraft. Additionally, the aerial assault destroyed hangars, fuel depots, and shore installations. Operation Hailstone inflicted a severe blow to the Japanese Imperial Navy and greatly diminished their naval power in the Pacific. The destruction of numerous warships, submarines, and aircraft significantly reduced the Japanese ability to project force and disrupted their logistical capabilities. Moreover, the successful American operation shattered the morale of the Japanese troops stationed at Chuuk Lagoon. The operation also demonstrated the effectiveness of carrier-based aviation as a dominant force in naval warfare. The American carriers played a pivotal role in the assault, proving their versatility and ability to strike enemy targets with devastating precision. This success further solidified the role of carriers as indispensable assets in future military operations. Furthermore, Operation Hailstone set the stage for subsequent Allied advances in the Pacific. By neutralizing Chuuk Lagoon as a Japanese naval stronghold, the operation allowed the United States to establish bases and expand its influence in the region. This paved the way for future offensives, including the retaking of the Philippines and the ultimate defeat of the Japanese Empire. Today, the sunken remnants of Operation Hailstone lie at the bottom of Chuuk Lagoon, serving as a testament to the brutal realities of war. The underwater ruins, including warships, aircraft, and other relics, attract divers and historians, offering a glimpse into this historic battle and the sacrifices made by both sides.

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Diving Chuuk

All the dives were guided and where possible (on most dives) we penetrated the wrecks. Our guide Bettewien was great and put us at ease on the deeper dives with his quiet gentle nature. He monitored our air consumption, depth and bottom time closely during the dive. He wasn't, however, overly controlling and let us explore the wrecks in our time and at a pace that was comfortable for us. His air bubble rings kept us entertained during the 10@5 safety stops.

The diving itself was fantastic! The water temperature was a constant 28°C no matter what the depth. There was no swell or surge and only an occasional wind chop. On some of the dives there was a very slight current, which wasn't difficult to swim against. The visibility was excellent, although not the 'Gin Clear' waters that places such as Palau are renown for. There are a lot of particles in the water which makes photography tricky due to the flash reflecting back off the particles and showing up as white spots on the shots.

Not only were the wrecks fantastic but the fish life was exceptional. There are Chromis of all sorts, including Green Puller (Chromis viridis) and Blue-green Puller (Chromis atripectoralis), Dascyllus everywhere especially Three-spot Dascyllus (Dascyllus trimaculatus), Headband Humbug (Dascyllus reticulatus) and Humbug Dascyllus (Dascyllus aruanus), some of the Pink Anemone Fish (Amphiprion perideraion) are residing in the biggest Magnificent Sea Anemones (Heteractis Magnifica) around. We saw heaps of Tall-fin or Teira Batfish (Platax teira), huge schools of Big-eye Trevally (Caranx sexfasciatus) and a plethora of Blue Damsel (Pomacentrus coelestis).

Our Three Favourite Wrecks


San Francisco Maru

This shipwreck was initially discovered by Jaques Cousteau during 1969, at which time it was not dived. It was located again during a 1973 fathometer survey and the ship's bell was used to confirm its identity. It is one of the most spectacular shipwrecks inb the world and often called the "Million Dollar Wreck" by divers speculating at the worth of the military cargo aboard.

Hoki Maru

Although the Hoki Maru is badly damaged in the forward sections, the aft No. 5 Hold contains items that can be found nowhere else on the wrecks of Chuuk; building equipment and trucks. There is an airport mule (tractor), and a row of trucks (about 3 ton in size) all stowed neatly together side by side at lower level. The wheels still rotate freely after 70 years submerged. Perhaps the most exciting find in the holds are two still intact John Deere bulldozers.


Shinkoku Maru

The Shinkoku Maru is one of the most interesting in the lagoon with vivid corals, and fish life along with fine arrays of shipboard artifacts. Night dives are supreme and rank with ‘best ever’. The soft corals and hydroids that emerge after dark turn Shinkoku Maru into a hanging garden and her medical bay is an interesting diversion along with arrays of engine and docking telegraphs on an upper bridge level. 

Other Wrecks of Chuuk

Chuuk Wrecks

The lagoon contains over 60 wrecks that have been largely untouched since the end of the war. The wrecks are now home to a variety of marine life, including coral, sharks, and schools of fish.


Exploring the Wrecks of Chuuk Lagoon is considered to be a unique and unforgettable experience for divers, as it offers a rare opportunity to see the remnants of a major naval battle and witness the impact of the war on the marine environment. 

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