Nongkhnum Island is the biggest river island in Meghalaya and the second biggest river island in Asia, after Majuli Island in Assam.

Located about 14 kms from Nongstoin, the district hqs. of West Khasi Hills, it is 20 to 25 sq. kms in area. Travelling on foot from Nongstoin through the villages of Lawse, Mawduh and Mawthar, it takes about two and a half-hours to reach the Island. There is a wooden bridge over the Weinia Fall to enter the Island.

The Island is formed by the bifurcation of Kynshi River into the Phanliang River and the Namliang River. At the point of divergence, there is a beautiful sandy shore about 100 sq. meters in area. The Phanliang River forms a beautiful lake adjacent to the sandy beach. This lake is about 400 to 500 sq. meters. The River then moves along and before reaching a deep gorge, forms a pretty fall about 60 meters high, called Shadthum Fall. At the bottom of the fall, there is a beautiful pool where a variety of fishes can be found. It then continues its journey and finally reunites with the Namliang River, near a place called Thongrin.

The Namliang River first flows towards the north and then changes its course towards the west. It then reaches a gorge and forms two narrow falls. The first one is called Riatsohkhe fall and is near Mawthar village. The second one is the wonderful and beautiful Weinia fall, which is about 60 meters high. The River then flows further west till it reunites with the Phanliang River on the western rocky shore and then flow towards the west. After a distance of about 10 kms from the Island, it reaches the deepest gorge and forms the longest fall in the region of about 335 to 340 meters high, called Langshiang fall.

The area surrounded by the two Rivers, i.e. Phanliang and Namliang forms the Nongkhnum Island. Within the Island, there are big trees and areas of grassland and natural playground suitable for playing football and golf and even for landing a helicopter. There are plenty of fishing pools, especially near the sandy shore, called Wei-Phanliang. Angling is the only way to enjoy as well as protect the fishes.