History of West Africa more states. Early human settlers arrived in West Africa around 12,000 BCE. In the fifth millennium, as the ancestors of modern West Africans began entering the area, the development of sedentary farming began to take place in West Africa. The Iron industry, in both smelting and forging for tools and weapons, appeared in Sub-Saharan Africa by 1200 BCE, and by 400 BCE, contact had been made with the Mediterranean civilizations, and a regular trade included exporting gold, cotton, metal, and leather in exchange for copper, horses, salt, textiles, and beads. Culture developed further with the Nok culture (1000 BCE to
Toei 12-000 series platform edge doors installed at every station. LCD information displays are provided above the doors. The trains entered service on 6 April 2015, with six units to be delivered by June 2016, replacing older 12-000 series trains. The last remaining first-batch trains (sets 01 to 06) are scheduled to be withdrawn by the end of June 2016. The two prototype cars, 12-001 and 12-002 are preserved at Chihaya Flower Park in Toshima, Tokyo. Toei 12-000 series The is an electric multiple unit (EMU) train type operated by the Tokyo subway operator Tokyo Metropolitan Bureau of Transportation (Toei) on the Toei