The Ngorongoro crater, one of the finest wilderness areas of Africa, originated from the caldera of an ancient volcano. The bottom of the crater is mainly a semiarid environment, while the outer slopes are covered by a montane evergreen forest.
A thick fog often clouds these slopes, particularly in the morning. This was probably the cause of the air accident that took the life of Michael Grzimek, son of the famous german naturalist Bernhard Grzimek, author of the book "Serengeti shall not die". Today they both rest on the border of the crater. A memorial pyramid of the Grzimeks stands near to this point.