Arusha Region in the context of "Narok County"

The Olduvai Gorge or Oldupai Gorge in Tanzania is one of the most important paleoanthropological localities in the world; the many sites exposed by the gorge have proven invaluable in furthering understanding of early human evolution. A steep-sided ravine in the Great Rift Valley that stretches across East Africa, it is about 48 km (30 mi) long, and is located in the eastern Serengeti Plains within the Ngorongoro Conservation Area in the Olbalbal ward located in Ngorongoro District of Arusha Region, about 45 kilometres (28 miles) from Laetoli, another important archaeological locality of early human occupation. The British/Kenyan paleoanthropologist-archeologist team of Mary and Louis Leakey established excavation and research programs at Olduvai Gorge that achieved great advances in human knowledge. The site is registered as one of the National Historic Sites of Tanzania.

The gorge takes its name from the Maasai word oldupai which means "the place of the wild sisal" as the East African wild sisal (Sansevieria ehrenbergii) grows abundantly throughout the gorge area. Twenty-five kilometers downstream of Lake Ndutu and Lake Masek, the gorge is the result of up to 90 m (300 ft) erosion cutting into the sediments of a Pleistocene lake bed. A side gorge, originating from Lemagrut Mountain, joins the main gorge 8 km (5.0 mi) from the mouth. This side gorge follows the shoreline of a prehistoric lake, rich in fossils and early hominin sites. Periodic flows of volcanic ash from Olmoti and Kerimasi helped to ensure preservation of the fossils in the gorge.

The Iraqw people (/ɪˈrɑːkuː/) are a Cushitic ethnic group inhabiting the northern Tanzanian regions. They dwell in southwestern Arusha and Manyara regions of Tanzania, near the Rift Valley. The Iraqw people then settled in the southeast of Ngorongoro Crater in northern Karatu District, Arusha Region, where the majority of them still reside. In the Manyara region, the Iraqw are a major ethnic group, specifically in Mbulu District, Babati District and Hanang District.

The Datooga (Wamang'ati in Maasai language meaning enemy, a name adopted into swahili) are a Nilotic ethnic people group from Tanzania that are closely related to the Kalenjin ethnicity in Kenya and Uganda, located in Karatu District of Arusha Region and historically in areas of southwest Manyara Region and northern Singida Region. In 2000, the Datooga population was estimated to number 87,978.

The Hadza, or Hadzabe (Wahadzabe, in Swahili), are a protected hunter-gatherer Tanzanian indigenous ethnic group, primarily based in Baray, an administrative ward within Karatu District in southwest Arusha Region. They live around the Lake Eyasi basin in the central Rift Valley and in the neighboring Serengeti Plateau. As descendants of Tanzania's aboriginal, pre-Bantu expansion hunter-gatherer population, they have probably occupied their current territory for thousands of years with relatively little modification to their basic way of life until the last century. They have no known close genetic relatives and their language is considered an isolate.

Since the first European contact in the late 19th century, governments and missionaries have made many attempts to settle the Hadza by introducing farming and Christianity. These efforts have largely failed, and many Hadza still pursue a life similar to their ancestors. Since the 18th century, the Hadza have come into increasing contact with pastoralist peoples entering Hadzaland, sometimes declining in population. Tourism and safari hunting have also affected them in recent years.

Ngorongoro Conservation Area (UK: /(ə)ŋˌɡɔːrəŋˈɡɔːroʊ/, US: /ɛŋˌɡɔːroʊŋˈɡɔːroʊ, əŋˌɡoʊrɔːŋˈɡoʊroʊ/) is a protected area and a UNESCO World Heritage Site located in Ngorongoro District, 180 km (110 mi) west of Arusha City in Arusha Region, within the Crater Highlands geological area of northeastern Tanzania. The area is named after Ngorongoro Crater, a large volcanic caldera within the area. The Ngorongoro Conservation Area Authority (NCAA), which administers the Ngorongoro Conservation Area (NCA), is an arm of the Tanzanian government and its boundaries follow the boundary of the Ngorongoro District in the Arusha Region. The western portion of the park abuts the Serengeti National Park (SNP). The area comprising the NCA, SNP, and Kenya's Maasai Mara game reserve is home to Great Migration, a massive annual migration of millions of wildebeest, zebras, gazelles, and other animals. The NCA also contains Olduvai Gorge, one of the most important paleoanthropological sites in the world.

Ngorongoro Conservation Area is one of the most popular attractions in Tanzania with 752,232 tourists visiting it in 2023.

Olbalbal is an administrative ward in the Ngorongoro District of the Arusha Region of Tanzania. The ward is home to the famous Olduvai Gorge. The ward covers an area of 7.893 square kilometres (3.048 sq mi) with an average elevation of 1,405 metres (4,610 ft).

In 2016, reports there were 5,387 people in the ward, from 8,969 in 2012, and 7,561 in 2002. The ward has 680 inhabitants per square kilometre (1,800/sq mi).

Ngorongoro District (Wilaya ya Ngorongoro, in Swahili) is one of seven districts in western Arusha Region of Tanzania. The district is bordered to the north by Kenya, to the east by Monduli District, the northeast by Longido District, and to the south by the Karatu District. The western border is the Serengeti District in Mara Region. Ngorongoro District is home to the Ngorongoro Crater and was named after it. It covers an area of 14,036 km (5,419 sq mi). The district is comparable in size to the land area of Timor Leste. The administrative seat is the town of Loliondo. The district is home to the Ngorongoro Conservation Area which is a UNESCO World Heritage Site. The district is also home to the third tallest mountain in the country, Mount Loolmalasin. According to the 2002 Tanzania National Census, the population of the Ngorongoro Region was 129,776. By 2012, the population of the district was 174,278. By 2022, the population had grown to 273,549.

Laetoli is a pre-historic site located in Enduleni ward of Ngorongoro District in Arusha Region, Tanzania. The site is dated to the Plio-Pleistocene and famous for its Hominina footprints, preserved in volcanic ash. The site of the Laetoli footprints (Site G) is located 45 km south of Olduvai Gorge. The location and tracks were discovered by archaeologist Mary Leakey and her team in 1976, and were excavated by 1978. Based on analysis of the footfall impressions "The Laetoli Footprints" provided convincing evidence for the theory of bipedalism in Pliocene Hominina and received significant recognition by scientists and the public. Since 1998, paleontological expeditions have continued under the leadership of Amandus Kwekason of the National Museum of Tanzania and Terry Harrison of New York University, leading to the recovery of more than a dozen new Hominina finds, as well as a comprehensive reconstruction of the paleoecology. The site is a registered National Historic Sites of Tanzania.

Dated to 3.7 million years ago, they were the oldest known evidence of hominin bipedalism at that time. Subsequently, older Ardipithecus ramidus fossils were found with features that suggest bipedalism. With the footprints there were other discoveries excavated at Laetoli including Hominina and animal skeletal remains. Analysis of the footprints and skeletal structure showed clear evidence that bipedalism preceded enlarged brains in Hominina. At a species level, the identity of the Hominina who made the trace is difficult to construe precisely; Australopithecus afarensis is the species most commonly proposed.

Kilimanjaro Region (Mkoa wa Kilimanjaro in Swahili) is one of Tanzania's 31 administrative regions. The regional capital and largest city is the municipality of Moshi. With the 3rd highest HDI of 0.640 in the country, Kilimanjaro is one among the top five most developed regions of Tanzania. According to the 2012 national census, the region had a population of 1,640,087, which was lower than the pre-census projection of 1,702,207. For 2002–2012, the region's 1.8 percent average annual population growth rate was the 24th highest in the country. It was also the eighth most densely populated region with 124 people per square kilometer. The most well-known tribes in the Kilimanjaro region are the Chaga.

The region forms part of the Northern Tourism Circuit in Tanzania. It is home to the Kilimanjaro National Park (which contains Mount Kilimanjaro), the Mkomazi National Park, the Pare Mountains, Lake Jipe, and Lake Chala. The region is bordered to the north and east by Kenya, to the south by the Tanga Region, to the southwest by the Manyara Region, and to the west by the Arusha Region.