Koninkrijksdag is observed on December 15, 2025. Koninkrijksdag is the commemoration of the signing of the Charter for the Kingdom of the Netherlands on 15 December 1954 in Aruba, Curaçao, the Netherlands, and Sint Maarten. When 15 December falls on a Sunday, the commemoration takes place on Monday 16 December. Kingdom Day is, unlike Koninginnedag, not an official national holiday, but government buildings are instructed to fly the flag of the Netherlands without pennant. (With material from: Wikipedia)
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