Mizoram is a land of rolling hills, valleys, rivers and lakes. As many as 21 major hill ranges or peaks of different heights run through the length and breadth of the state, with plains scattered here and there. The average height of the hills to the west of the state are about . These gradually rise up to to the east. Some areas, however, have higher ranges which go up to a height of over . Phawngpui Tlang also known as the Blue Mountain, situated in the southeastern part of the state, is the highest peak in Mizoram at . About 76% of the state is covered by forests, 8% is fallows land, 3% is barren and considered uncultivable area, while cultivable and sown area constitutes the rest. Slash-and-burn or jhum cultivation, though discouraged, remains in practice in Mizoram and affects its topography. The State of Forest Report 2017 states that Mizoram has the highest forest cover as a percentage of its geographical area of any Indian state, being 86.27% forest.