South Asia consists of those countries located between the Himalaya range of mountains on the north and the Indian Ocean on the south, and between the Indus river Valley and the Ganga Valley (east to west). The coastal line of Indian Ocean is divided between the Bay of Bengal (in the east) and the Arabian Sea (in the west). South Asia , with its extensive, triangular-shaped landmass, is sometimes referred to as "the Indian Subcontinent".