Meghalaya rewards groups that do not mind walking. The double-decker living root bridge at Nongriat sits at the bottom of a long stone stairway, the Umngot river at Dawki runs glass-clear in winter, and the drive to Cherrapunji passes a waterfall every few kilometres.
Roughly 3,000 to 3,500 steps down from Tyrna and the same back up. It is best done over two days with a night at a Nongriat homestay — groups that attempt it as a day trip almost always regret the climb back in the afternoon. Carry cash; there is nothing to withdraw from down there.
Fly into Guwahati and hire one vehicle for the whole trip. Shillong, Cherrapunji, Dawki and Mawlynnong are connected by good roads, but public transport between them is thin and unpredictable for a group on a schedule.
The Umngot river is only clear outside the monsoon, roughly November to March; in the rains it runs brown and boating stops. Cherrapunji is among the wettest places on earth between June and September, which is spectacular for waterfalls and miserable for trekking. Village homestays have very few rooms and no online booking, so call ahead once the group size is final.