Marine Day (海の日): How and Why Japan Pay Homage to the Oceans

Marine Day, otherwise known as Umi no Hi (海の日), falls on the third Monday of July. It’s a public holiday in Japan dedicated to showing appreciation and giving thanks to the ocean and its blessings.

Also as Sea Day or Ocean Day in English, Marine Day was first observed in 1996, making it a toddler in comparison to most of Japan’s national holidays. This was the year the day, once known as Marine Memorial Day, became a national holiday. Since 2003, it’s officially celebrated on the third Monday of every July. Although this holiday is still relatively new, there is no shortage of ways that you can pay homage to all of the world’s oceans, from the Atlantic to the Pacific.

This year, Marine Day falls on July 18. Read on to learn more about the history of this holiday and how you can get involved.

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How Did Marine Day Start?

Japan Ocean Day

The roots of Marine Day stretch back to July 20, 1876, when the Meiji Emperor returned to the Port of Yokohama safely after a sea voyage across Tohoku and Hokkaido. Over 60 years later, the expedition was commemorated by naming the July 20 ‘Marine Memorial Day. However, it was only in 1995 that the Japanese government propose this to become a national holiday in the summer months dedicated to the sea, and its name was aptly changed to its current title.

The Happy Monday System legislation — a Japanese law that moved a number of public holidays in Japan on Mondays — moved Marine Day to the third Monday of July in 2003. This allows Japan to appreciate the oceans over a three-day weekend.

Why is Gratitude for the Oceans Important in Japan?

Undeniably, water is vital for our survival. So it’s probably logical that we should all be grateful for our seas, lakes and rivers. But, how many of us actually take the time to intentionally practice gratitude for the oceans?

Japan is the only country in the world that has a public holiday dedicated to the blessing of the oceans.

Why? Well, perhaps this is rooted in Japan’s deep connection with loving the land and the oceans – which are important aspects of Shintoism. Religion has especially strong ties to nature, considering all of its elements to be tied to deities. With Japan being comprised of around 6,000 smaller islands, the recreational and health benefits of the ocean can be easily observed by most of us.

Now, Marine Day is amongst several other holidays dedicated to nature, such as Greenery Day and Mountain Day.

How is Marine Day (Umi no Hi) in Japan Celebrated?

Unlike other holidays, Marine Day is a relatively new celebration in Japan, so there’s no real ‘correct’ way to celebrate it — at least traditionally. That said, there are some popular ways to celebrate the day of the sea in an unspoken agreement. Befitting to the name, we celebrate it by doing water-related activities.

Because Marine Day falls in the middle of summer, people use this opportunity to take a trip to the beach. Because it’s a long weekend, day trips are popular options. People will snorkel, surf and dive with their friends and family.

Another way to spend time at the sea is ‘mud-ball throwing’, which has become quite popular over the last few years. If you don’t mind getting your hands dirty, you can literally give something back to the oceans by throwing dried mud-balls filled with ‘Effective Micro-organisms” (EMs) into the water. These balls help to break down and eliminate sea grime.

Or for something slightly more refined, the national aquariums host special water-related events.

During this time, Japan’s Maritime Self-Defense Force also dresses their ships with flags and banners to mark the occasion.

How You Can Enjoy Marine Day in Tokyo

Odaiba Marine Park

At Odaiba Marine Park, you can treat your eyes to a spectacular array of lanterns that line the foreground to the Rainbow Bridge. This is called the Marine Day Lantern Festival, held in Odaiba every year. Volunteers would light up more than 50,000 colored lanterns on the bridge, making the entire sight even more breathtaking.

Yokohama Port

Head down to Yokohama Port, where Marine Day officially began, for fireworks. However, due to the pandemic, the Yokohama Sparkling Twilight has been canceled as a precaution. In 2022, the fireworks will be suspended too, but let’s hope that this year will be the last.

Beach in Tokyo

For beaches and ocean views, some of the easiest sea-front locations to reach are Odaiba, Yokohama, Kamakura, Enoshima and Chiba, which are all accessible within a one-hour train ride from Tokyo JR Station.

Aquariums in Tokyo

Visit one of Tokyo’s three Aquariums: Sumida, Sunshine or Tokyo Sealife. The national aquariums in Japan usually organize special events, water sports competitions, water shows, and activities relating to the sea.

If you prefer to avoid crowds, a stroll along the Sumida, Kanda-gawa or Arakawa River may work better for you.

How do Japanese celebrate Marine Day?

Marine Day is a relatively new celebration in Japan, so there’s no real ‘correct’ way to celebrate it, but most people celebrate it by doing water-related events and activities: going to the beach, visiting the aquarium, snorkeling, surfing or diving.

When is Marine Day in Japan celebrated?

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