Oldupai Gorge (originally misnamed Olduvai) is the most famous archaeological location in East Africa, and has become an essential visit for travelers to Ngorongoro or Serengeti.
At Laetoli, west of Ngorongoro Crater, hominid footprints are preserved in volcanic rock 3.6 millions years old and represent some of the earliest signs of mankind in the world. Three separate tracks of a small-brained upright walking early hominid. Australopithecus afarensis, a creature about 1.2 to 1.4 meters 
high, were found. Imprints of these are displayed in the Oldupai museum.
More advanced descendants of Laetoli's hominids were found further north, buried in the layers of the 100 meters deep Oldupai Gorge. Excavations, mainly by the archaeologist Louis and Mary Leakey, yielded four different kinds of hominid, showing a gradual increases in brain size and in the complexity of their stone tools. The first skull of Zinjanthropus, commonly known as 'Nutcracker Man' who lived about 1.75 millions years ago, was found here. The most important find include Home habilis, Zinjathropus and the Laetoli footprints.
The excavation sites have been preserved for public viewing and work continues during the dry seasons, coordinated by the Department of Antiquities. One may visit Oldupai at all times of the year. It is necessary to have official guide to visit the excavations. At the top of the Gorge there is small museum, a sheltered area used for lectures and talks, toilets and a cultural boma. Local Maasai souvenirs are also available.
Thus, Oldupai and Laetoli makes the Ngorongoro Conservation Area an important place in the world for the study of human origins and human evolution.
The Ngorongoro Conservation Area (NCA) - where people and their early ancestor have co-existed with wildlife for nearly four million years. This World Heritage Site and International Biosphere Reserve encompasses a spectacular mosaic of landscape that includes the breath-taking Ngorongoro Crater and the legendary Serengeti - the annual host of the World's highest concentration and diversity of migratory animals numbering nearly two-million strong. As if this wasn't enough, the NCA also contains two important and internationally-known fossil and archaeological sites: Laetoli and Olduvai Gorge. Both continue to contribute significantly to understanding of humankind's physical, behavioral and technological evolution.
The Olduvai Gorge Museum and Visitors Center offer numerous educational exhibits, including fossils and artifacts of our human ancestors and skeletons of many extinct animals who shared their world. There are also informative lectures, special guided archaeological sites tours, native handcrafts and a well-stocked bookshop. See and learn about our collective human origins when we were once all Africans.
See and touch a huge cast of actual footprints made by our early human ancestors (hominins ) known as "Lucy" Australopithecus afarensis. The prints of three hominins were miraculously preserved in muddy ash deposited by volcanic eruptions and hardened by the sun some 3.6 million years ago.
Made by feet little different than our own, they proved conclusively that these creatures stood and walked upright (bipedally) with a human-like stride a million years before the invention of stone tools and the initial growth in hominin brain size. It's undoubtedly one of the most astounding and important scientific discoveries of our time.
A complete room of the Olduvai Museum devoted to the hominin footprint trail.
Some 30,000 years ago, splitting of the earth's surface by violent geological activity and millennial of erosion by seasonally flowing streams incised the nearly 250 foot (90m) canyon known as Olduvai Gorge. These natural forces exposed a remarkably rich geological chronicle of human ancestry and the evolution of the Serengeti ecosystem. It was here that Mary and Louis Leakey unearthed the first well-dated artifacts and fossils of some of our earliest human ancestors after over 30 years of painstaking work. These include the famous Zinjanthropus (Australopithecus boisei) skull, homo habills, the presumed maker of the numerous early stone tools in the 1.8 to 1.6 million year-old deposits, and homo erectus, the larger bodied, larger brained hominin that preceded the earliest modern humans (Homo sapiens). Special archaeological tours guided by the Department of Antiquities personnel are available and include the remarkable Shifting Sands.
Similar to modern-day East African lakes, the nearly two million year-old paleolake Olduvai once teemed with large predators and gigantic plant-eaters. Clearly our ancestors lived and evolved in a brutal world where sudden death potentially lurked at every turn. They successfully competed against such dangerous competitors by seizing an opportunity created by large carnivores with the aid of a few sharp stones and refuge trees.
Somewhere in the East Africa's Great Rift Valley over two million years ago, a bipedal ape picked up two rounded fist-sized stones. Forcibly striking one against the other, he created a sharp-edged implement and several razor-edged stone flakes. By design or accident, this was the world's most important technological breakthrough because it helped make us human. Their ability to cut open the thickest of animal hides and process and consume the nutritious flesh and bone marrow may have been the metabolic catalyst for increased brain size and our successful transition from apes to humans. These crude but effective tools and later stone implements are on display in the Olduvai Museum. The full, up-to-date story of Laetoli and Olduvai Gorge and our early ancestors is available in a newly published booklet available in the Museum book shop.
The first skull of Zinjanthropus, commonly known as 'Nutcracker Man' who lived about 1.75 millions years ago, was found here.
Some 30,000 years ago, splitting of the earth's surface by violent geological activity and millennial of erosion by seasonally flowing streams incised the nearly 250 foot (90m) canyon known as Olduvai Gorge.
Somewhere in the East Africa's Great Rift Valley over two million years ago, a bipedal ape picked up two rounded fist-sized stones. Forcibly striking one against the other, he created a sharp-edged implement and several razor-edged stone flakes.
Similar to modern-day East African lakes, the nearly two million year-old paleolake Olduvai once teemed with large predators and gigantic plant-eaters.