Usually held on the third Monday in July, Umi No Hi, or Marine Day is a special holiday celebrating the sea – which due to the Olympics in 2020-2021 has been moved to the following Thursday, forming a 4-day weekend!

As the beaches in Japan are seen as being ‘closed’ throughout much of the year, the occasion of Marine Day marks a certain watershed for us swimmers. It’s the beginning of that time of year when co-workers, friends and supermarket checkout workers won’t look at you like you’re a mad person for swimming in the sea.

It’s a short honeymoon - as soon as September begins you’re back to being seen as a hopeless lost cause, who will inevitably end up as a hearty breakfast for killer jellyfish.

Anyhow. Marine Day.

The holiday has its roots in the Meiji era. It was 1876, and the emperor took a steamship voyage around the northern regions of Japan in a boat made in Scotland. Wonderful. Designated a special day in 1941, in 1995 it finally became a national holiday for everyone. Now always held on the same Monday of the year it also coincides with the long-awaited “sayonara tsuyu” (goodbye rainy season).

So if you find yourself fancy free in Tokyo this Monday, what should you do?

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One option, if the trek to the beaches seems too much of an effort, is a city outdoor pool. It’s a solid, convenient and reasonably priced option. Watch out though, Umi No Hi is a work and school holiday, which means everywhere will be mobbed.

If the idea of being surrounded by screaming, high-on-ice-cream kids is your worst nightmare try and pick somewhere more dedicated to lane swimming. Usually these ones will have some space to read a book at the side too.

Check out our Tokyo Pool Guide if you’re in the capital.

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Another option is to go to the beach. It seems only right and proper on Marine Day, after all? They will mostly be crowded, of course, but they’re ultimately way more spacious than the pools. A great advantage to hitting the more commercial of Japan’s beaches on Monday is that they take on a sort of festival atmosphere, with live bands, bars, barbeques, food stands all there for you to spend your pocket money on.

Japan is spoilt for good beaches, and by now the water is warm n’ friendly. To really get in the spirit of it why not head to Enoshima or Kamakura? The water isn’t the cleanest, the clearest or the deepest but you’re guaranteed a genki (upbeat) crowd and some solid entertainment, and this holiday is all about the seaside after all.

Both these places are easy to get to, have nice shopping streets to investigate and a range of après swim options. Check out our page on Enoshima and our page on Kamakura for more.

These are both great spots to visit for a day, a weekend or even longer, and only a couple of hours train ride away from Tokyo.

If you fancy a different sort of change of scenery you could hit up some mountain wilderness. There are some gorgeous rivers to jump in within easy reach of Central Tokyo.

What’s more, they’ll be quieter if you’re not into crowds: Mountain Day, Japan’s newest holiday, is next month!

If you do end up doing something interesting, anywhere in Japan, do share it with us on instagram, twitter, facebook and email.

Happy Holidays!


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Swimming In Japan

Swimming in Japan is a space to share and find out how and where to swim in Japan’s abundant rivers, lakes, beaches, pools and more.

We love exploring and are always looking for new swim spots, and co-adventurers if you think this is you and you want to join the team.


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