There are about 115 volcanic craters in Tanzania. The biggest of them is the crater of the volcano NgororoNoro. The caldera, which arose about 2.5 million years ago, today is a unique place in its peculiarities. A crater with a depth of about 600 km and a diameter of about 22 km is a recreational area, untouched by the human hand. A lost world where a closed ecosystem was created. Where the inhabitants can not get out, as the height of the rocks above the crater is more than 300 m. Here the animals are born, they live their whole life and die. The origin of the name of the crater is interesting. In the Masai language there is the word "Nkoronkoro". So the ancient Masai called their warriors, who came to protect these lands from hostile invaders. Their alarming drums made a sound, the imitation of which is that word. According to statistics, conducted by scientists, there live about 30 000 individuals of different animals. There are more than 55 species of different mammals, as well as about 100 varieties of birds. Territory NgoroNgoro Crater Conservation Area (Reserve "Crater of Volcano NgoroNgoro") occupies 8292 hectares. Once upon a time there were many crocodiles in the crater. But the tribes of the indigenous people - the Masai, living in the territory, eventually exterminated them. Now in the reserve there are no such reptiles at all. Still some 30 years ago here lived more than 100 individuals of rhinoceroses. In the countries of Asia, Africa and some others, it is believed that the medicine from the rhinoceros horns returns the lost male power. Due to the horns, hunting for these animals was very popular, as a result of which, there were only 17 individuals left today. From poachers they are guarded by a service of 50 rangers. Because of poaching, the number of animal dwellers in the crater has sharply decreased, and therefore in 1979 Ngorongoro was inscribed on the UNESCO World Heritage List as the greatest natural monument. Later, in 1981 received the status of "biosphere reserve". The world inside the crater is rich and diverse. A bush grows along the edges of the rocks. The caldera itself is a moist savannah with a short dewy grass, which is an excellent pasture for herbivores. Huge herds of buffaloes, zebras, various species of antelopes migrate from place to place. Lions, elephants, hyenas, baboons, hippos - that's not a complete list of interesting animals of the reserve. Wild dickey, striped jackal, reed goats, white and black rhinoceroses, impala, congonies, Bush bush can also meet visitors to the national park. The bird world of Ngororo is also rich. Ostriches, flycatchers, flamingos, nectaries and other rare and unusual species of birds inhabit the park. The deepest area of ​​the volcanic crater is filled with water - the Mage Lake, around which there are many marshes. At the watering hole, and just lying around in the mud, African elephants and rhinoceroses come here. NgoroNgoro National Park is rightly called "Paradise on Earth" and is considered the eighth wonder of the world.