The birthday of Crown Prince Christian of Denmark is observed in Denmark every October 15. This day is marked as an official flag flying day, during which the national flag is displayed at official buildings and ships throughout the country. Christian, born on October 15, 2005, became Crown Prince and heir apparent to the Danish throne following his father's ascension on January 14, 2024. His 18th birthday in 2023 was particularly significant, as it included a changing of the guard at Amalienborg and a gala dinner at Christiansborg Palace, attended by 200 young people from across the realm. The prince's birthday celebration reflects the longstanding tradition of honoring royal family members in Denmark.