The Iranian plateau or Persian plateau is a geological feature spanning parts of Central Asia, South Asia, West Asia and the Caucasus. It makes up part of the Eurasian plate, and is wedged between the Arabian plate and the Indian plate. The plateau is situated between the Zagros Mountains to the west, the Caspian Sea and the Köpet Dag to the north, the Armenian Highlands to the northwest, the Strait of Hormuz and the Persian Gulf to the south, and the Indian subcontinent to the southeast. As a historical region, it includes Parthia, Media, Persis, and some of the previous territories of Greater Iran. The Zagros form the plateau's western boundary, and its eastern slopes may also be included in the term. The Encyclopædia Britannica excludes "lowland Khuzestan" explicitly and characterizes Elam as spanning "the region from the Mesopotamian plain to the Iranian Plateau". Stretching from the Caspian Sea in the northwest to the Sulaiman Mountains in the southeast, the Iranian Plateau extends nearly 2,000 kilometres (1,200 mi). It encompasses the majority of Iran, all of Afghanistan, and the parts of Pakistan that are situated to the west of the Indus River, covering an area of some 3,700,000 square kilometres (1,400,000 sq mi). In spite of being called a plateau, it is far from flat, and contains several mountain ranges; its highest point is Noshaq in the Hindu Kush at 7,492 metres (24,580 ft), and its lowest point is the Lut Desert to the east of Kerman, Iran, at below 300 metres (980 ft).