Several occassions but with different timing happens in Punakha. Punakha Drupchen - 23rd - 27th Feb, Punakha Tshechu - 28th Feb - 2nd March and Punakha Talo Tshechu - 7th - 9th April.
Punakha Summary
Punakha Drupchen 23rd - 27th Feb
Punakha Tshechu 28th Feb - 2nd March
Punakha-Talo Tshechu - 7th- 9th April