Koobi Fora refers primarily to a region around Koobi Fora Ridge, located on the eastern shore of Lake Turkana in the territory of the nomadic Gabbra people. According to the National Museums of Kenya, the name comes from the Gabbra language.
The ridge itself is an outcrop of mainly Pliocene/Pleistocene sediments. It is composed of claystones, siltstones, and sandstones that preserve numerous fossils of terrestrial mammals, including early hominin species. Presently, the ridge is being eroded into a badlands terrain by a series of ephemeral rivers that drain into the northeast portion of modern Lake Turkana. In 1968 Richard Leakey established the Koobi Fora Base Camp on a large sandspit projecting into the lake near the ridge, which he called the Koobi Fora Spit.
A subsequent survey and numerous excavations at multiple sites established the region as a source of hominin fossils shedding light on the evolution of man over the previous 4.2 million years. Far exceeding the number of humanoid fossils are the non-humanoid fossils giving a detailed look at the fauna and flora as far back as the Miocene.
Consequently the government of Kenya in 1973 reserved the region as Sibiloi National Park, establishing a headquarters for the National Museums of Kenya on Koobi Fora Spit. The reserve is well-maintained and is well-guarded by friendly but armed park police. Protection of sites and especially of wildlife are of prime concern. Exploration and excavation continue under the auspices of the Koobi Fora Research Project (KFRP), which collaborates with a number of interested universities and individuals across the world.
The simple hierarchy of scientific places for Koobi Fora is the following: Koobi Fora is the region; the region is divided into fossil collecting areas (e.g., Area 102, 103, 140, etc.); within fossil collection areas there are archaeological sites (e.g., FxJj 1, FxJj 10, etc.) and hominid palaeontological localities, which are usually named after the National Museum of Kenya accession number assigned to the important bones found. For example, in Area 131 hominid skull KNM-ER 1470 was found. The fossils found here, including all the non-human ones, are assigned to the 1470 locality.
Fossils are labelled with a KNM (Kenya National Museums) accession number, assigned on no other basis than the order in which it was assigned. The number may be preceded in scholarly literature by KNM, KNM ET or KNM ER, where ET and ER stand for East Turkana and East Rudolf, respectively, or just plain ER. Some notable areas are as follows.
The first archaeological site, i.e., FxJj 1, was found in Area 105. It is nicknamed the KBS site for Kay Behrensmeyer Site, after Kay Behrensmeyer, the researcher who first found stone tools there. This site is also the place where the first tuff was found, i.e., the KBS Tuff.
It is known as the location of skull 1470, discovered by Bernard Ngeneo in 1972, reconstructed by Meave Leakey, later reconstructed and named Homo habilis by Richard Leakey, as possibly the first of the genus Homo, and finally Homo rudolfensis. Richard Leakey found it 45 m below the 1.89 my KBS tuff; thus, it is older than that date, but is conventionally dated to it.