Wadi Al-Hitan (Arabic: وادي الحيتان, Whale Valley) is a palaeontological site in the Al Fayyum Governorate of Egypt.
It was designated a UNESCO World Heritage Site in July 2005 for its invaluable fossil remains of the earliest, and now extinct, suborder of whales, the archaeoceti.
These fossils represent one of the major stories of evolution: the emergence of the whale as an ocean-going mammal from a previous life as a land-based animal.This is the most important site in the world for the demonstration of this stage of evolution. It portrays vividly the form and life of these whales during their transition.
The number, concentration and quality of such fossils here is unique, as is their accessibility and setting in an attractive and protected landscape.
The fossils of Al-Hitan show the youngest archaeocetes, in the last stages of losing their hind limbs. They already display the typical streamlined body form of modern whales, whilst retaining certain primitive aspects of skull and tooth structure. Other fossil material in the site makes it possible to reconstruct the surrounding environmental and ecological conditions of the time.