The Ngorongoro Crater is more than 15 miles in diameter. More than 25,000 large mammals roam the grasslands and forests of the crater floor, including lion, elephant and black rhino. Alas, it can also be crowded with people nowadays. The Serengeti can be reached from the crater by charter plane or a five-hour drive. This magnificent reserve is more than 200 miles long and is surrounded by contiguous conservation areas. Expect to see every imaginable predator, all waiting their turns to feed on the more than 2 million migrating herbivores. The place that is generally acknowledged to provide the most unforgettable chimpanzee sightings is Mahale Mountains National Park, a remote and beautiful reserve located on the eastern shore of Lake Tanganyika.