Meghalaya is one of the Seven Sister States of northeast India. The state of Meghalaya is mountainous, with stretches of valley and highland plateaus, and it is geologically rich. It consists mainly of Archean rock formations. These rock formations contain rich deposits of valuable minerals like coal, limestone, uranium and sillimanite.
Meghalaya has many rivers. Most of these are rainfed and seasonal. The important rivers in the Garo Hills region are Ganol, Daring, Sanda, Bandra, Bugai, Dareng, Simsang, Nitai and the Bhupai. In the central and eastern sections of the plateau, the important rivers are Khri, Umtrew, Digaru, Umiam or Barapani, Kynshi (Jadukata), Umngi, Mawpa, Umiam Khwan, Umngot, Umkhen, Myntdu and Myntang. In the southern Khasi Hills region, these rivers have created deep gorges and several waterfalls.
The elevation of the plateau ranges between 150 m (490 ft) to 1,961 m (6,434 ft). The central part of the plateau comprising the Khasi Hills has the highest elevations, followed by the eastern section comprising the Jaintia Hills region. The highest point in Meghalaya is Shillong Peak, which is a prominent IAF station in the Khasi Hills overlooking the city of Shillong. It has an altitude of 1961 m. The Garo Hills region in the western section of the plateau is nearly plain. The highest point in the Garo Hills is Nokrek Peak with an altitude of 1515 m.
With average annual rainfall as high as 12,000 mm (470 in) in some areas, Meghalaya is the wettest place on earth.[29] The western part of the plateau, comprising the Garo Hills region with lower elevations, experiences high temperatures for most of the year. The Shillong area, with the highest elevations, experiences generally low temperatures. The maximum temperature in this region rarely goes beyond 28 °C (82 °F),[30] whereas sub-zero winter temperatures are common.