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San Francisco Maru Dive of Truk Lagoon (Chuuk Lagoon Wrecks)

San Francisco Maru wreck inside her hold showing ammunition shells

The San Francisco Maru was sunk during Operation Hailstone in 1944

This short article about the San Francisco Maru wreck is to provide you with a few basic details about this Japanese World War II wreck ship. This San Francisco Maru is one of the many Truk Lagoon wrecks for scuba divers to dive in Chuuk Lagoon, which is in Micronesia.

Truk Lagoon is the name these Pacific lagoons and islands were named in 1944 when they were in Japanese occupation. However, the name of Truk Lagoon was changed in 1990 to Chuuk Lagoon.

Scuba divers seem to use these two names synonymously. Whilst the correct name is Chuuk Lagoon, at the time San Francisco Maru was sunk it was named Truk Lagoon.

The best way to dive Truk Lagoon is by a scuba diving liveaboard. You can check the latest and best deals on Truk Lagoon liveaboards using the following window:

The wrecks are is now dived by scuba divers across the world.

Truk Lagoon dive liveaboards table

This list of Truk Lagoon liveaboards is in descending customer rating order, followed by Scuba Diving Luxury Rating (SDE Lux Rating, see below), so the liveaboards with the highest customer rating and the best SDE lux rating will be at the top of the list. If you want to change the list order, use the “Sort by” dropdown below.

Sort by:
Total Records Found: 3, showing 10 per page
Discover LiveaboardCustomer RatingSDE Lux Rating %Flexible BookingDive CoursesDietary RequirementsNitroxGear Rental
Review: SS Thorfinn; Book: SS Thorfinn 8.8 88% YES YES YES YES YES
Review: MV Truk Master; Book: MV Truk Master 7.9 65% YES NO YES YES YES
Review: MV Pacific Master; Book: MV Pacific Master 0 56% YES YES YES YES YES

The Scuba Diving Earth Luxury Rating (SDE Lux Rating) is explained on each liveaboard review when you click the “Discover Liveaboard” link, and is my own Liveaboard Luxury Rating I’ve assigned to all liveaboards. Choosing between liveaboards is helped by customer scores, and if you get stuck choosing between two or three liveaboards, where each one has a high customer score out of 10, you can use the SDE Luxury Rating to help narrow down your choice.

Think about it like using when searching for the best hotel. also use a customer score where each customer rates hotels out of 10. This is similar to the liveaboard customer rating, which is also rated out of 10. But let’s say you only like to stay in hotels rated 8 and above on, but you also want the hotel to have WIFI or parking, or to have a swimming pool etc. The features each hotel has is usually secondary to the score out of 10.

San Francisco Maru Dive Wreck Bow Gun

Details of San Francisco Maru dive of the Truk Lagoon wrecks

The San Francisco Maru wreck dive is considered to be one of the most exciting dives in Chuuk Lagoon. She is packed with World War II artefacts. These include gas masks to a full size battle tank. But unfortunately for most scuba divers the San Francisco wreck is a very deep dive.

More Reading: Recovery of the Junkers Jumo 211 (recovery of underwater artifacts)

To enjoy this dive you need to be able to dive to at least 50 metres (164 feet).

The superstructure is at around 42 metres (140 feet) deep. But the deck is at 50 metres (164 feet) deep. But to really enjoy the dive on the San Francisco Maru you’ll need to go deeper than 50 metres.

To see the location of the San Francisco Maru on a map please follow this link to: Truk Lagoon wreck map. search all Truk Lagoon-scroll

Due to the depth of the San Francisco Maru wreck and because there’s so much to see, this wreck is best explored on several dives. This wreck is best dived as a technical decompression stop dive by those trained to do so.

  • The San Francisco Maru wreck is sitting upright in 42-64 metres (140-210 feet) depth of water.
  • Divers will get to see a bow gun, trucks, tanks, mines, shells, bombs, aircraft engines, ammunition, china and depth charges on stern.
  • The San Francisco Maru wreck was a passenger cargo ship.
  • She measured 117 metres (385 feet).
  • She was 5,831 tons and operated in world trade operations in minerals such as coal, bauxite, and phosphate for transportation to the Japanese Empire.
  • The word ‘Maru’ in Japanese ship naming protocol designates a merchant vessel.
  • This passenger-Cargo ship was built in 1919 for Yamashita Kisen Kabushiki Kaisha.
San Francisco Maru wreck inside her hold showing ammunition shells

Comments on San Francisco Maru wreck

The first reported finding of the San Francisco Maru was on Jacques Cousteau expedition there in 1969. It was during this expedition that the true extent of what was to be found in Chuuk Lagoon was uncovered. Not least the human remains found on a few Truk Lagoon wrecks.

The San Francisco Maru dive gives you a true sense of what it was like back on the 18th February 1944. Which is when she was sunk during Operation Hailstone in World War II.

The dive site is good as the water is mostly clear giving divers a good visibility dive.

She was sank by a bomb that hit the bridge house. This means this is not intact. But this is a blessing for divers diving the San Francisco Maru dive. If the bomb had hit one of the holds she would have been completely destroyed.

When you look inside her holds you’ll see a store of ammunition crates and artillery shells, torpedo bodies, aircraft bombs, cordite containers, hemispherical mines and depth charges. Had the ammunition store suffered a direct hit this dive would not be what it is today.

Visit the engine rooms and see the huge steel coal fired boilers with a huge engine to go with them.

To understand more about what happened at Truk Lagoon, please take a read of this article what happened at Truk Lagoon in 1944.

San Francisco Maru Truk Lagoon Micronesia wreck video

This is a video of the San Francisco Maru truk Lagoon wreck.

This is Truk Lagoon – The San Francisco Maru in 4K UHD
Captain Lance Higgs from the S.S. Thorfinn, one of the most knowledgeable people on the history of the many wrecks in Truk Lagoon, gives interesting background information on some of the very famous wrecks located here.

I hope you enjoyed this article about San Francisco Maru wreck of Truk Lagoon

I’d love to hear from you. Tell us about your adventures of diving and snorkeling, in the comments below. Please also share your photos. Either from your underwater cameras or videos from your waterproof Gopro’s!

If this article hasn’t answered all of your questions. If you have more questions either about snorkeling or scuba diving (or specifically about San Francisco Maru wreck of Truk Lagoon), please comment below with your questions.

There will also be many more articles about scuba diving (and snorkeling) for you to read and learn about these fabulous sports.

Have fun and be safe!

San Francisco Maru Dive of Truk Lagoon (Chuuk Lagoon Wrecks)

Article written by Russell Bowyer who has been a scuba diver since diving on the Great Barrier Reef in Australia in 1989. After his first dive he trained as a BSAC diver in the UK. He attained his Diver Leader certification with BSAC. He then went on to become a scuba diving instructor, teaching others how to dive and was voted as Diving Officer and Treasurer for the Saffron Walden BSAC club too. Russell has dived all over the world, including the UK, on liveaboards in the Red Sea, the Caribbean, South Africa and the USA. Russell is experienced in all dive types, including drift diving, deep dives that involved decompression stops and recreational dives too.

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