The Nepal, Bhutan and Tibet Tour by Air is an 18-day cultural tour that links the three Himalayan countries, flying in and out of both Bhutan and Tibet from Kathmandu. You fly Kathmandu to Paro for four nights in Bhutan, spend five days in Nepal between Chitwan National Park and Pokhara, then fly Kathmandu to Lhasa for four nights in Tibet. Hotels are 3-star throughout. You can join a fixed weekly departure or book private dates for 2 to 10 people, and the highest point is the 4,794 m Kamba La on a day trip to Yamdrok Lake. You never sleep higher than Lhasa at 3,656 m.
In Nepal, Day 2 covers four of the Kathmandu Valley's UNESCO monument zones: Kathmandu Durbar Square, Swayambhunath, Boudhanath and Pashupatinath. Patan and Bhaktapur follow on Day 7, after you get back from Bhutan. Then the road runs south to Chitwan, where a jeep safari, a dugout canoe on the Rapti River and a Tharu village walk fill two days among one-horned rhinos and 500-plus bird species. Pokhara comes next, with sunrise over Machhapuchhre from Sarangkot and the walk up to the World Peace Pagoda above Phewa Lake.
Bhutan gets four unhurried nights. From Paro you drive to Thimphu, cross the Dochula pass (about 3,100 m) to Punakha Dzong at the meeting of the Pho Chhu and Mo Chhu rivers, and finish with the hike to Taktsang, the Tiger's Nest monastery, set on a cliff roughly 900 m above the Paro valley. Your daily Sustainable Development Fee, Bhutanese visa, guide and all meals in Bhutan are part of the price.
Lhasa is the last stop, reached by air. The 21-day overland route was built around the road into Tibet at Kerung and a 5,220 m pass. This one lands you in Lhasa in about 75 minutes, gives you a gentle first afternoon on the Barkhor, then three full days: the Potala Palace and Jokhang Temple, the debating courtyard at Sera and the old Gelug seat of Drepung, and the turquoise water of Yamdrok Tso. Swotah's licensed Tibetan partner arranges the Tibet Travel Permit and your Chinese group visa from Kathmandu.