Marine Day, also known as Sea Day or Ocean Day, is observed in Japan every July 20. This national holiday celebrates the sea and its resources, commemorating the voyage of Meiji Emperor in 1876 aboard the iron steamship Meiji-Maru. The holiday was established in 1941 by Shozo Murata, the then-Minister of Communications, and was celebrated unofficially until it was designated a national holiday in 1995. Initially celebrated on July 20, the date was shifted to the first Monday in July in 2003 as part of the Happy Monday System, creating three-day weekends. Marine Day encourages appreciation for the ocean and its contributions to Japanese culture and economy.