Somalia was likely one of the first lands to be settled by early humans due to its location. Hunter-gatherers who would later migrate out of Africa likely settled here before their migrations.[74] During the Stone Age, the Doian and Hargeisan cultures flourished here.[75][76][77][74][78][79] The oldest evidence of burial customs in the Horn of Africa comes from cemeteries in Somalia dating back to the 4th millennium BCE.[80] The stone implements from the Jalelo site in the north were also characterized in 1909 as important artifacts demonstrating the archaeological universality during the Paleolithic between the East and the West.[81] According to linguists, the first Afroasiatic-speaking populations arrived in the region during the ensuing Neolithic period from the family's proposed urheimat ("original homeland") in the Nile Valley,[82] or the Near East.[83] The Laas Geel complex on the outskirts of Hargeisa in northwestern Somalia dates back approximately 5,000 years, and has rock art depicting both wild animals and decorated cows.[84] Other cave paintings are found in the northern Dhambalin region, which feature one of the earliest known depictions of a hunter on horseback. The rock art is dated to 1,000 to 3,000 BCE.[85][86] Additionally, between the towns of Las Khorey and El Ayo in northern Somalia lies Karinhegane, the site of numerous cave paintings, which collectively have been estimated to be around 2,500 years old.[87][88] The camel is believed to have been domesticated in the Horn region sometime between the 2nd and 3rd millennium BCE. From there, it spread to Egypt and the Maghreb.[89] Antiquity and classical era Main article: Somali architecture Men from Punt carrying Gifts, Tomb of Rekhmire. Ancient pyramidical structures, mausoleums, ruined cities and stone walls, such as the Wargaade Wall, are evidence of an old civilization that once thrived in the Somali peninsula.[90][91] This civilization enjoyed a trading relationship with ancient Egypt and Mycenaean Greece since the second millennium BCE, supporting the hypothesis that Somalia or adjacent regions were the location of the ancient Land of Punt.[90][92] The Puntites native to the region traded myrrh, spices, gold, ebony, short-horned cattle, ivory and frankincense with the Egyptians, Phoenicians, Babylonians, Indians, Chinese and Romans through their commercial ports. An Egyptian expedition sent to Punt by the 18th dynasty Queen Hatshepsut is recorded on the temple reliefs at Deir el-Bahari, during the reign of the Puntite King Parahu and Queen Ati.[90] In the classical era, the Macrobians, who may have been ancestral to Somalis, established a powerful kingdom that ruled large parts of modern Somalia. They were reputed for their longevity and wealth, and were said to be the "tallest and handsomest of all men".[93] The Macrobians were warrior herders and seafarers. According to Herodotus' account, the Persian Emperor Cambyses II, upon his conquest of Egypt in 525 BC, sent ambassadors to Macrobia, bringing luxury gifts for the Macrobian king to entice his submission. The Macrobian ruler, who was elected based on his stature and beauty, replied instead with a challenge for his Persian counterpart in the form of an unstrung bow: if the Persians could manage to draw it, they would have the right to invade his country; but until then, they should thank the gods that the Macrobians never decided to invade their empire.[93][94] The Macrobians were a regional power reputed for their advanced architecture and gold wealth, which was so plentiful that they shackled their prisoners in golden chains.[94] During the classical period, the Barbara city-states of Mosylon, Opone, Mundus, Isis, Malao, Avalites, Essina, Nikon and Sarapion developed a lucrative trade network, connecting with merchants from Ptolemaic Egypt, Ancient Greece, Phoenicia, Parthian Persia, Saba, the Nabataean Kingdom, and the Roman Empire. They used the ancient Somali maritime vessel known as the beden to transport their cargo. The Beden is a fast, ancient Somali single or double-masted maritime ship. After the Roman conquest of the Nabataean Empire and the Roman naval presence at Aden to curb piracy, Arab and Somali merchants agreed with the Romans to bar Indian ships from trading in the free port cities of the Arabian peninsula[95] to protect the interests of Somali and Arab merchants in the lucrative commerce between the Red and Mediterranean Seas.[96] However, Indian merchants continued to trade in the port cities of the Somali peninsula, which was free from Roman interference.[97] For centuries, Indian merchants brought large quantities of cinnamon to Somalia and Arabia from Ceylon and the Spice Islands. The source of the cinnamon and other spices is said to have been the best-kept secret of Arab and Somali merchants in their trade with the Roman and Greek world; the Romans and Greeks believed the source to have been the Somali peninsula.[98] The collusive agreement among Somali and Arab traders inflated the price of Indian and Chinese cinnamon in North Africa, the Near East, and Europe, and made the cinnamon trade a very profitable revenue generator, especially for the Somali merchants.[96] Birth of Islam and the Middle Ages Main articles: Somali aristocratic and court titles, Ifat Sultanate, Walashma dynasty, Sultanate of Mogadishu, Adal Sultanate, and Ajuran Sultanate The Silk Road extending from China to southern Europe, Arabia, Somalia, Egypt, Persia, India, and Java Islam was introduced to the area early on by the first Muslims of Mecca fleeing prosecution during the first Hejira with Masjid al-Qiblatayn in Zeila being built before the Qiblah towards Mecca. It is one of the oldest mosques in Africa.[99] In the late 9th century, Al-Yaqubi wrote that Muslims were living along the northern Somali seaboard.[5] He also mentioned that the Adal Kingdom had its capital in the city.[5][100] According to Leo Africanus, the Adal Sultanate was governed by local Somali dynasties and its realm encompassed the geographical area between the Bab el Mandeb and Cape Guardafui. It was thus flanked to the south by the Ajuran Empire and to the west by the Abyssinian Empire.[101] Throughout the Middle Ages, Arab immigrants arrived in Somaliland, a historical experience which would later lead to the legendary stories about Muslim sheikhs such as Daarood and Ishaaq bin Ahmed (the purported ancestors of the Darod and Isaaq clans, respectively) travelling from Arabia to Somalia and marrying into the local Dir clan.[102] In 1332, the Zeila-based King of Adal was slain in a military campaign aimed at halting Abyssinian emperor Amda Seyon I's march toward the city.[103] When the last Sultan of Ifat, Sa'ad ad-Din II, was also killed by Emperor Dawit I in Zeila in 1410