Umbrella Day, or Kasa no Hi, is observed in Japan every June 11. Established by the Japan Umbrella Promotion Association (JUPA) in 1989, this day marks the beginning of the rainy season, known as tsuyu, and aims to promote the umbrella industry. The celebration highlights the cultural and functional significance of umbrellas in Japanese life, with activities including retail promotions, media campaigns focused on umbrella history and etiquette, and design contests. Historically, umbrellas in Japan have evolved from oil-paper types introduced during the Asuka period to modern transparent plastic designs popularized in the 20th century. Although Umbrella Day may appear commercial, it reflects Japan's cultural tendency to honor everyday objects, emphasizing their importance in daily life.