This is the most impacting monastery incrusted in a high mountain. It is called in Bhutanese Dzong Taksang (Dzong means monastery, and Taksang is “The Tiger Nest”). It is the most revered in the whole Bhutan because Padmasambhava, the 8th century Indian holy monk who introduced Buddhism in Tibet, stayed there during his hazardous journey accros the Himalaya.
You will need at least 2 hours to get there from Paro (if you are a good trekker), plus 2 more to come back. It suffered a tragic sinister in 1998, when it was burnt down.