National Submarine Day
April 11
About National Submarine Day
National Submarine Day is observed on 11 April each year in the United States, commemorating the date the US Navy purchased its first modern commissioned submarine. On 11 April 1900, the Navy acquired the Holland VI, a vessel designed by Irish-American inventor John Philip Holland, marking the beginning of the submarine era in American naval history. The day honours the crews who have served aboard submarines and recognises the technological innovation that has shaped modern defence.
What is National Submarine Day?
National Submarine Day is an annual observance honouring the history and heritage of submarine warfare in the United States. The day marks the anniversary of the US Navy’s acquisition of the Holland VI on 11 April 1900, which was subsequently commissioned as USS Holland (SS-1). Since that milestone, submarines have played a pivotal role in American military strategy, from both World Wars through the Cold War and into the present day. The observance is supported by veteran organisations, the US Navy Submarine Force, and military history enthusiasts across the country.
When is National Submarine Day?
National Submarine Day falls on 11 April every year. In 2026, that is a Saturday. The date is fixed, chosen to align with the anniversary of the Holland VI purchase in 1900, and does not change from year to year.
The Story Behind National Submarine Day
The story of National Submarine Day begins with John Philip Holland, an Irish-born engineer who emigrated to the United States in 1873. Holland was fascinated by the potential of underwater vessels and spent decades developing submarine designs. After several prototypes, he launched the Holland VI on 17 May 1897 at Navy Lieutenant Lewis Nixon’s Crescent Shipyard in Elizabeth, New Jersey. The vessel was 16 metres long and powered by a gasoline engine on the surface and an electric motor when submerged.
The US Navy purchased the Holland VI on 11 April 1900 for $150,000 and commissioned it as USS Holland (SS-1). It was the Navy’s first modern submarine, capable of diving to depths of over 20 metres and carrying a single torpedo tube and a pneumatic dynamite gun. While modest by modern standards, the Holland VI proved that submarines could be practical military vessels, and the Navy quickly ordered additional boats of similar design.
In 1969, Senator Thomas J. Dodd of Connecticut introduced a bill to formally designate 11 April as National Submarine Day. The bill passed the Senate and was introduced in the House in 1970, though no formal presidential proclamation was issued. Despite this, the day has been widely observed since 1970 by veteran organisations, naval bases, submarine memorial associations, and the broader military community. National Military Appreciation Month in May provides another opportunity to honour the contributions of submarine crews.
The US submarine fleet grew dramatically through the 20th century. During World War II, American submarines sank over 1,300 enemy vessels and played a decisive role in the Pacific theatre. The launch of USS Nautilus (SSN-571) in 1954, the world’s first nuclear-powered submarine, transformed naval warfare by allowing vessels to remain submerged for months at a time. Today, the US Navy operates a fleet of approximately 70 submarines, including ballistic missile submarines that form a cornerstone of the nation’s nuclear deterrent.
How to Get Involved in National Submarine Day
There are several ways to mark National Submarine Day, whether you have a personal connection to submarine service or simply an interest in naval history:
- Visit a submarine museum – Several decommissioned submarines are preserved as museum ships across the United States, including USS Bowfin in Pearl Harbor, USS Torsk in Baltimore, and USS Growler in New York City. These museums offer tours and educational programmes.
- Thank a veteran – If you know someone who has served on a submarine, take a moment to thank them for their service. Submarine crews operate in some of the most demanding conditions in the military.
- Watch a documentary or film – Films like “Crimson Tide,” “The Hunt for Red October,” and “Das Boot” offer dramatic portrayals of submarine warfare. Documentaries about the USS Nautilus and Cold War submarine operations provide factual accounts of this fascinating history.
- Read about submarine history – Books such as “Blind Man’s Bluff” by Sherry Sontag and Christopher Drew offer gripping accounts of submarine espionage during the Cold War.
- Support veteran organisations – Donate to groups that support submarine veterans and their families, such as the United States Submarine Veterans organisation.
- Learn about submarine technology – Modern submarines are marvels of engineering. Explore how nuclear propulsion, stealth technology, and advanced sonar systems work.
- Share the day on social media – Post facts, photos, or personal stories about submarine service using the hashtags below.
Noteworthy Facts About Submarines
- The USS Holland (SS-1), purchased on 11 April 1900, was 16 metres long and cost $150,000, roughly equivalent to $5.5 million today.
- USS Nautilus (SSN-571), launched in 1954, was the world’s first nuclear-powered submarine and made the first submerged transit of the North Pole in 1958.
- During World War II, US submarines comprised less than 2% of the Navy but sank over 55% of all Japanese maritime losses.
- Modern US Navy Ohio-class submarines can remain submerged for up to 90 days at a time, limited mainly by food supplies rather than fuel.
- The Silent Service is the nickname for the US submarine force, reflecting the secretive nature of submarine operations.
Frequently Asked Questions
What is National Submarine Day?
National Submarine Day, observed on 11 April, commemorates the US Navy’s purchase of its first modern submarine, the Holland VI, in 1900. The day honours submarine crews and the history of underwater naval warfare.
When is National Submarine Day in 2026?
National Submarine Day falls on Saturday, 11 April 2026.
Why is 11 April significant for submarines?
On 11 April 1900, the US Navy purchased the Holland VI from inventor John Philip Holland. It was commissioned as USS Holland (SS-1), becoming the Navy’s first modern submarine and launching the American submarine programme.
Spread the Word
Help honour the history of submarine service by sharing National Submarine Day with others. Use the hashtags #NationalSubmarineDay and #NationalSubmarineDay2026 on social media. You can also use #SubmarineDay and #SilentService to join the wider conversation.
Related Awareness Days
- National Military Appreciation Month – Observed throughout May, this month honours the men and women who serve in all branches of the US armed forces.
- Memorial Day – Held on the last Monday of May, this day remembers those who have died in military service to the United States.
- National Maritime Day – Celebrated on 22 May, this day recognises the contributions of the American merchant marine and maritime industry.
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