After Taktsang , Punakha is definitely the most popular monument in Bhutan . Once you have crossed the picturesque bridge that spans the river and gone through the heavy wooden door that guards the entrance, I advise you to take the time to saunter in this fortress where monks and civil servants mix and mingle in a sumptuous setting.
The mural paintings located in the temples in the dzong will plunge you into the rich Buddhist universe, a world populated by mandalas, Buddha and other tantric divinities inherent to Bhutan .
If you go there early enough in the morning you might get a chance to observe the monks' prayers, if not I suggest you stroll up and down the gardens to discuss with the students, ever happy to exchange with foreigners visiting the country.
Do not hesitate, either, to venture outside the temple to take the suspension bridge that straddles one of the two rivers, thrills and a panorama on Mount Everest guaranteed!