Olduvai Gorge is an exceptionally rich archaeological site, preserving one of the best records of human history spanning nearly 2 Ma. Paleoanthropologists have found hundreds of fossilized bones and stone tools in the area dating back millions of years, leading them to conclude that humans evolved in Africa.
Olduvai is a misspelling of Oldupai, a Maasai word for a wild sisal plant that grows in the area. The gorge is located in the Great Rift Valley, between the Ngorongoro Crater and the Serengeti National Park. It is 30 miles from Laetoli, another fossil-rich area. Olduvai Gorge has formed about 30,000 years ago, the result of aggressive geological activity and streams.
The site has yielded abundant human and animal fossils and stone artifacts preserved in well-dated stratigraphic sequence. The quantity, quality, and geological context of paleontological and archaeological data provide a yardstick for rates of evolutionary changes in human form and stone tool technology. Over four hominin species, including the holotypes for Paranthropus “Australopithecus” boisei (Zinjanthropus) and Homo habilis, as well as remains of Homo erectus and prehistoric Homo sapiens have been discovered at the site (Leakey 1971). The hominin record is consistent with the evolution of stone tool technology from the Oldowan to Acheulean, Middle Stone Age, and Later Stone Age industries.
The steep ravine is about 30 miles (48.2 km) long and 295 feet (89.9 meters) deep, not quite large enough to be classified as a canyon. A river cuts through several layers to form four individual beds, with the oldest estimated at about 2 million years old.
The site is significant in showing the increasing developmental and social complexities in the earliest humans, or hominins, largely revealed in the production and use of stone tools. Prior to tools, evidence of scavenging and hunting can be noted—highlighted by the presence of gnaw marks that predate cut marks—and of the ratio of meat versus plant material in the early hominin diet. The collecting of tools and animal remains in a centralized area is evidence of developing social interaction and communal activity. All these factors indicate an increase in cognitive capacities at the beginning of the period of hominids transitioning to hominin—that is, to human—form, and behavior.
Homo habilis, probably the first early human species occupied Olduvai Gorge approximately 1.9 million years ago (mya); then came a contemporary australopithecine, Paranthropus boisei, 1.8 mya, followed by Homo erectus, 1.2 mya. Our species Homo sapiens, which is estimated to have emerged roughly 300,000 years ago, is dated to have occupied the site 17,000 years ago
At Laetoli, west of Ngorongoro Crater, hominid footprints are preserved in volcanic rock 3.6 million 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 increase 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 million years ago, was found here. The most important find include Home habilis, Zinjathropus and the Laetoli footprints.
Olduvai Gorge monument and museum
In July of 2019, the Olduvai Gorge Monument was erected at the turnoff to Olduvai Gorge from the road which connects Ngorongoro Conservation Area and Serengeti National Park (the route traveled by safari-goers). The monument was designed and planned by paleoanthropologists Nicholas Toth, Kathy Schick, and Jackson Njau at the invitation of the Tanzanian government in order to celebrate this important site and to attract visitors to the gorge and its new museum. The monument consists of two large-scale models of fossil skulls that sit atop a large pedestal with an informative plaque mounted on the side of the pedestal. The fossil skulls depicted are Paranthropus boisei and Homo habilis, two contemporary species that were first discovered at Olduvai Gorge. Schick, Toth, Njau and Joshua Mwankunda (NCAA Cultural Heritage Manager) commissioned the celebrated Tanzanian artist Festo Kijo to create the two large concrete skulls which he modeled using life-size fossil casts provided by the researchers. The large-scale models created by Kijo are each 6 feet tall and weigh 5,000 pounds. The monument project was funded by the Stone Age Institute and the John Templeton Foundation, in partnership with the Ngorongoro Conservation Area Authority (NCAA).
The Olduvai Gorge Museum, located 5 km beyond the monument, is situated on the rim of the gorge at the junction of the main gorge and the side gorge. As one of the largest onsite museum in Africa, the museum provides educational exhibits related to the gorge and its long history.
The Details
A visit to the Olduvai Gorge focuses on the smart new museum, opened in October 2017, and overlooking the gorge. Whilst there you will also have a chance to listen to a short presentation by a resident guide.
Explore the different sections of the museum to discover the history of the site and learn about the various fossils to be found here. See a replica of the nearby Laetoli Footprints, which provide some of the earliest evidence of bipedalism; learn about the hominines and prehistoric mammals that lived in the area; and chat with a resident expert about the significance of the area as well as the current research. We found that it takes around an hour to explore the museum, but there is no time limit and you can spend as much time looking around as you wish.
For a small tip of around $10 USD, you can drive down into the gorge itself and visit the sites where Mary and Louis Leakey discovered early hominin remains. This is around a ten-minute drive, and you would typically spend no more than 20 minutes here. You’ll go with a member of staff, not a guide, but there is an information board at the site. It is also sometimes possible to visit active dig sites, as Olduvai Gorge is the focus of a number of ongoing studies. Teams of researchers typically visit in the dry season, between June and October, so you may be able to chat with the scientists involved and hear about the latest findings to come out of the gorge.
A 30-minute drive from Olduvai you can find a curious phenomenon, a shifting sand dune. This dune is formed from fine volcanic ash, which due to its high iron content is highly magnetic. This means that the dune clings together, and acts as a single unit as it slowly moves across the landscape. Researchers have tracked the movement of the dune over time, finding it that it moves around 10m a year, blown by the prevailing wind.
Start time: Visits to Olduvai Gorge normally take place as you drive between the Ngorongoro Crater and the Serengeti, or vice versa, so timings will depend on when you are passing by.
Where is Olduvai Gorge?
Olduvai Gorge is located in the eastern Serengeti ecosystem in the Ngorongoro Conservation Area which is a UNESCO World Heritage Site. The Serengeti Plains of Northern Tanzania is renowned for the biggest annual Wildebeest migration in the world.
Olduvai Gorge is about 48km (30 miles) long. There is a museum on the edge of the ravine where visitors can learn more about fossil excavation and see exhibits of finds from the gorge and its surroundings. One hall is dedicated to the Leakey family while a second hall depicts information for another of Mary Leakey’s discoveries, the Laetoli fossilized footprints trail – this archaeological site is located 45km (28 miles) south of Olduvai Gorge.