Topographically Ceylon is a detached portion of the South Indian peninsula. It divides into two climatic regions, known as the Dry and Wet Zones; the latter occupies approximately the south-western quarter of the island. By African standards, dry and wet are relative terms and there may be over 80 inches of rain in the Dry Zone. Even so, rainfall tends to be concentrated and long periods without rain occur. The Wet Zone receives rain during both monsoons, the Dry Zone during the north-east monsoon only. Monsoons sometimes fail and serious droughts are not uncommon.