The Manas is the best place in the world to see golden langr monkeys, but you may also catch a glimpse of elephants and tigers. The main drwaback is that the park is way out there and that it requires sepcial permits to visit.

Bumthang
Lhuntsi
Manas game sanctuary
Paro
Phuntsholing
Punakha
Tashigang
Thimphu
Wangdiphodrang