Bhutanese calendar holidays are either Lunar (the majority of Bhutan public holidays) or Solar.
Bhutanese lunar holidays consist of a Month-Day pair and the specification of whether the holiday should be observed on the leap month and/or leap day (if applicable).

Zhabdrung Kuchhoe (Bhutan)
Bhutanese solar holidays consist of a Mansion/Sub-Mansion pair.
Thrue Bab (Bhutan)
See also: Recurrence Rules Options.