Why it's incredible: The lake is one of the largest on Earth, but it lies beneath several miles of ice. Lake Vostok is a giant lake in Antarctica that is similar in size to North America's Lake ...

The Helmand River flows across Afghanistan and enters Iran’s Hamoun wetlands in the Sistan-Baluchestan province after originating in the Hindu Kush Mountains near Kabul. Lake Hamoun used to be one of ...