Ngorongoro Crater, located in northern Tanzania, in close proximity to the Serengeti National Park, is not actually a crater, but a volcanic caldera. It is also a UNESCO World Heritage Site and based on fossils found in the area it is believed that various hominids have walked this land for more than 3 million years.
The crater is 610 meters deep and forms a natural enclosure for close to 25000 wild animals. The big fives can be found here, as well as virtually all the individual species found in this part of Africa.
The shot below is panorama taken from close to the top of the crater, while we were on our way out after a full day of safari.