Wadi Al-Hitan (Whale Valley)

Whales once walked, and the proof lies in Egypt's Western Desert. Wadi Al-Hitan — Whale Valley — holds an unrivalled concentration of fossils of the archaeocetes, the earliest whales, caught mid-transition with their shrinking hind limbs still attached. No other place documents so vividly how a land mammal became a creature of the open ocean, and the surrounding fossil beds even preserve traces of the ecosystems those first whales swam through. UNESCO inscribed the valley as a natural World Heritage Site in 2005.