Umi no Hi, or Marine Day, is a national holiday in Japan that celebrates the ocean and the vital role it plays in the country’s culture and daily life. For those living in Japan, it’s more than just a day off—it’s a chance to enjoy summer, explore seaside spots, and reflect on Japan’s deep connection with the sea.
In this guide, you’ll learn what Umi no Hi is all about, when it’s celebrated, and how to make the most of this special day.
Table of Contents
For more information on other Japanese seasonal customs, please refer to the article below.
Chapter 1: What is Umi no Hi?
Umi no Hi, or Marine Day, is a national holiday in Japan celebrated on the third Monday of July. It was established to give thanks for the ocean’s blessings and to reflect on the importance of the sea to Japan’s prosperity as a maritime nation.
Surrounded by water on all sides, Japan is one of the countries most deeply connected to and benefited by the sea. Marine Day encourages people to appreciate the ocean’s gifts and to nurture a spirit of respect and care for the sea.
Chapter 2: When is it Celebrated?
Umi no Hi (Marine Day) is celebrated on the third Monday of July, making it part of a long weekend every year. Since it always falls on a Monday, it follows Saturday and Sunday—creating a perfect opportunity for a three-day weekend ideal for short trips or family outings.
Here are the upcoming dates for Marine Day:
2025: July 21 (Monday)
2026: July 20 (Monday)
2027: July 19 (Monday)
Many people take advantage of this time to travel, visit the beach, or participate in seasonal events.
Chapter 3: Things to Do on Umi no Hi
Unlike some Japanese holidays, Umi no Hi (Marine Day) doesn’t have traditional customs or ceremonies. However, many people take this chance to enjoy the sea and summer-related activities. It’s the perfect time to appreciate Japan’s rich connection to the ocean.
Popular ways to spend Marine Day include:
Visiting aquariums: Great for families and couples. Top choices include
Kaiyukan (Osaka)
Maxell Aqua Park (Tokyo)
Okinawa Churaumi Aquarium
Going to the beach: Japan has beautiful coastlines. Popular beach destinations include
Kamakura and Enoshima (Kanagawa Prefecture)
Shirahama (Wakayama Prefecture)
Zushi Beach (Kanagawa)
Amami Islands and Okinawa
Enjoying marine sports: Try activities like stand-up paddleboarding, snorkeling, kayaking, or diving, especially in areas like
Okinawa
Izu Peninsula (Shizuoka Prefecture)
Setouchi (Inland Sea area)
Whether it’s a relaxing walk by the sea, a day at an aquarium, or trying something adventurous in the water, Marine Day is a great opportunity to reconnect with the ocean.
Marine Day is a great chance to enjoy the ocean—whether at the beach, an aquarium, or through marine sports.
Have a question or want to share how you spent Marine Day? Leave us a comment!
Japan’s summer is extremely hot, so wherever you go, don’t forget to bring water, a hat, and other heat protection.
For more tips, see the article below.
