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FriApr 11

National Submarine Day – April 11, 2025

National Submarine Day is on April 11 and it celebrates the purchase of the USS Holland, the first modern commissioned submarine. This day is important to the submarine community as it honors the US Navy’s purchase of their first modern submarine, but life underwater isn’t all that glamorous. Often, crews are out at sea for months at a time and return when food supplies run low. Subs can be cramped with tedious tasks to complete daily, and some might not always be the best of friends with everybody on board. It’s not just enemies and the sea they have to contend with.

History of National Submarine Day

National Submarine Day celebrates the United States government’s purchase of the Holland VI, but it actually wasn’t the first submarine the US had. The USS Alligator was the first known submarine owned by the United States. On August 10, 1832, Brutus Villeroi completed work on his submarine, possibly called the Nautilus, and showcased his invention off the coast of France. 

At that time, the submarine was known as a “fish boat” that measured 10 feet 6 inches in length and 3 feet 7 inches at the widest diameter. The fish boat submerged, reaching depths of 20 feet and it was an impressive display. In 1861, Villeroi designed the USS Alligator that the United States sank in the ocean on April 2, 1863, after losing a battle with a brutal storm.

On April 11, 1900, the US government purchased the Holland VI for $150,000 designed by Irish-American inventor John Phillip Holland and commissioned on October 12, 1900. It was commanded by Lieutenant H.H. Caldwell and deemed the first modern submarine with a host of impressive components all in one vessel. 

It had dual propulsion systems, a fixed longitudinal center of gravity, separate main and auxiliary ballast systems, a hydrodynamically advanced shape, and a modern weapon system. It’s reported that the Holland VI was decommissioned on November 21, 1910, and marked an important breakthrough for the US Navy.

Senator Thomas J. Dodd introduced a bill to the US Senate in 1969 that would make April 11 National Submarine Day. President Richard Nixon was in office at that time and there were no records of his proclamation. It might have passed the Senate and introduced it to the house in 1970, but the exact date is unclear. All the same, the US Navy and other organizations celebrated the day that commemorated the Holland VI and the contributions to modern warfare it made.

National Submarine Day timeline

Submarine Day Emerges

The US Navy and other organizations celebrate the US Navy’s first modern submarine purchase, the USS Holland.

November 21, 1910
Naval Goodbye

The Holland VI is officially decommissioned and struck from the Naval Vessel Register.

April 11, 1900
Modern Marvel

The US government purchases the Holland VI modern submarine for around $150,000.

April 2, 1863
The Sunken Place

The first submarine purchased by the US government, the USS Alligator, sinks in the Atlantic Ocean.

National Submarine Day FAQs

How long is a day on a submarine?

A submarine “day” lasts 18 hours and is split into three six-hour shifts. So a submariner may work for six hours and train, maintain equipment or sleep for 12 hours.

What is the point of a submarine?

They provide intelligence and underwater protection for surface ships and can detect and lay mines more efficiently than any other navy vessel. Submarines provide a means to land special forces in hostile regions and, if fitted with suitable weapons, can strike land targets.

How do submarines dispose of human waste?

“Sanitary Tanks” inside the pressure hull hold the wastewater from toilets, showers, etc and are usually pumped overboard. Submarines can also empty some of the sanitary tanks by pressurizing them and discharging them overboard.

How To Celebrate National Submarine Day

  1. Take a tour of a real submarine

    Have you ever thought about what life is like on a submarine? Get an idea of sea life by going on a tour of a real submarine. You’ll learn firsthand about the duties onboard, the challenges they face, how submarines operate, and you can visualize what life would be like as a submariner.

  2. Visit a Navy museum

    If you’re a fan of history, visiting a Navy museum is the perfect place to go for all the information you desire. Learn about the epic battles and operations and the Naval events that changed the course of history. You’ll get your questions answered by experts who have all the information at their disposal.

  3. Curate your own Naval experience

    If you can't tour a submarine or a Navy museum, go on a virtual tour from home. Online videos are the next best thing. Conduct your own research and deep dive into specific Naval history that piques your curiosity using online videos. If you want an even more relaxing experience, have a submarine movie day with “The Hunt for Red October”, “U-571”, and more to get Hollywood’s take on submarine action.

5 Interesting Facts About National Submarine Day

  1. The subway

    The submarine is also a type of sandwich made with a long roll of bread, meats, vegetables, and spreads.

  2. Women weren't allowed

    Up until 2010, women could not be assigned to submarine crews because of the limited habitability and privacy onboard a submarine.

  3. Nuclear future

    Many of John Holland’s ideas couldn’t be applied to the submarine at the time and they had to wait for nuclear power to include them in the design.

  4. The first submarine

    The first known submarine was created in 1620 by Cornelius Drebbel.

  5. Leagues above the rest

    The German epic film “Das Boot” by director Wolfgang Peterson is considered by many as the best submarine film ever made.

Why We Love National Submarine Day

  1. Submarines are instrumental in history

    Without the battles that have been waged at sea, the course of world history would be remarkably different. World War II, the Korean War, and the Indo-Pakistan War of 1971 all used submarines with varying results. Had the US Navy not been so formidable, modern-day society would have taken a different shape.

  2. There’s something mysterious about them

    There’s no mistaking that submarines are fascinating because, by their design, they are elusive. These vessels sink into unfathomable depths as they roam through the waters gathering data and completing covert missions. It’s no wonder why there are so many movies about them.

  3. The best Navy in the world

    The sheer might of the United States Navy is impressive and commands respect. Without a doubt, the United States has the most powerful Naval force in all the world with over 300,000 active personnel and another 100,000 in reserve. Because they hold the top spot, they’re on a constant mission to advance their operations to keep it that way.

National Submarine Day dates

2025April 11Friday
2026April 11Saturday
2027April 11Sunday
2028April 11Tuesday
2029April 11Wednesday

Let’s get social

Here are some special hashtags for the day.

#submarine #underwater #ocean #navy

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