The Ngorongoro Crater is the world’s largest unbroken volcanic caldera and is regarded as the 8th wonder of the world. It is one of the most diverse and fascinating areas of Tanzania and has been given the status of a World heritage site and International Biosphere Reserve. The fertile slopes and steep forest-covered walls are home to approximately 30,000 animals including the rare black rhino. The various ecosystems found within the 260 square kilometre crater floor sustain Cape buffalo, elephants, wildebeest, zebras, elands, gazelles, hippos, numerous bird species as well as a high concentration of predators. Although birdlife is generally good throughout the year, from November to April, migratory birds from Europe and Northern Africa are present and many resident birds are in breeding plumage.