The Emperor’s Birthday, or Tenno Tanjobi (天皇誕生日), is a national holiday which currently takes place on 23 December. This date changes when a new emperor ascends the throne. This year, 2018, will be the last year 23 December will be celebrated as Emperor Akihito’s birthday, as his abdication has been announced for 30 April 2018.
The previous Emperor’s Birthday was celebrated on 29 April, birthday of Emperor Hirohito. That day has been renamed Greenery Day in 1989, and is known as Showa Day since 2007. Is it thus probable that 23 December will be known as Heisei Day from 2019 on.
Every year on the Emperor’s Birthday, there is a public ceremony held at the Imperial Palace in Tokyo. The Emperor accompanied by the Empress and other Imperial Family members appear on a balcony and acknowledges the birthday wishes of the present crowd. This, as well as the New Year address on 2 January are the only times the public is allowed to enter the inner grounds of the Imperial Palace of Tokyo.