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National Submarine Day

Celebrate National Submarine Day with a dive into the depths of underwater exploration!

Sunday

April 2027

Last updated February 7, 2026 · by the Holiday Calendar Team

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YEARLY DATEApril 11

OBSERVED INUnited States

CATEGORYCareers

SUBCATEGORYMilitary

INTRO

Introduction

PHOTO

Get ready to celebrate National Submarine Day on April 11! This day celebrates the invention of the submarine, which has played a major role in naval warfare since its inception. The first submarine was built by Dutch inventor Cornelius van Drebbel in 1620, and it is believed that he and his crew took several submerged trips along the Thames River. Since then, submarines have become an integral part of modern military strategy due to their stealth capabilities and ability to navigate underwater for extended periods of time.

TIMELINE

National Submarine Day Timeline

Invention of Submarine

Cornelius van Drebbel invents the first navigable submarine, making several submerged voyages along the Thames River.

Turtle Submarine

During the American Revolutionary War, the "Turtle" – American's first submarine – is deployed but fails to sink a British warship.

Submarine In Combat

The Confederate submarine H.L. Hunley becomes the first to sink an enemy warship during the American Civil War.

U.S. Navy's First Submarine

The U.S. Navy commissions its first submarine, the USS Holland.

German U-Boats in WWII

During World War II, Germany's U-boats launch sustained submarine attacks on Allied supply ships.

First Nuclear-Powered Submarine

The USS Nautilus, the world's first operational nuclear-powered submarine, enters service for the U.S. Navy.

GET INVOLVED

How to Celebrate National Submarine Day

Watch a submarine movie

Gather your family and friends, pop some popcorn and watch a classic submarine movie like “Das Boot” or “Hunt for Red October”.

VISIT

Visit a submarine museum

Check out the nearest Navy base or research online to find a local museum that has a submarine exhibit. It’s a great way to learn about the history of submarines, their technology, and even get an up close view of one.

READ

Read a submarine novel

If you are more of an indoor person, why not curl up with a good book? Pick up a submarine novel such as “The Hunt for Red October” by Tom Clancy or “Below” by Ryan Lockwood.

PLAY

Play a submarine game

For an interactive experience, try playing a computer game like Silent Hunter 4 or Sub Command: Akula Seawolf 688(I). Dive in and let the adventure begin!

EAT

Eat submarine sandwiches

No celebration is complete without food, right? Head to your favorite local sandwich shop and order yourself a classic sub sandwich in honor of National Submarine Day.

WHY THIS DAY MATTERS

Why National Submarine Day is Important

Helps protect ocean environments

Submarines are an important tool for marine research and conservation efforts around the world. By studying ocean environments and ecosystems, submariners help us better understand our planet’s waters and how best to preserve them for future generations.

Celebrates naval history

National Submarine Day is a special day to recognize and honor the history of submarine warfare. It pays tribute to all of the brave servicemen who have served on submarines, fought in battles, and put their lives on the line protecting our freedoms.

Recognizes modern technology

Submarines have come a long way since their first use in war. Modern subs are some of the most sophisticated underwater vessels ever created and feature cutting edge technologies such as sonar navigation and deep diving capabilities.