There are currently 20 countries and 22 territories that do not have a permanent natural river flowing within them, though some of them have streams or seasonal watercourses such as wadis.[1] The Arabian Peninsula is the largest subregion in the world without any permanent natural river.The Chinese special administrative region of Macau has no permanent natural rivers other than a small man-made canal named Canal Dos Patos (鴨涌河).Due to environment issues, this small canal is currently being backfilled with land by the local government.Eventually, this small canal will cease to exist.