The accumulation of seemingly minor geographical inaccuracies in African studies leads to an increase in the number of errors that can significantly distort the understanding of the history of West Africa. The article considers some of them: confusion with geographical coordinates in medieval Arabic sources, which continued into the 20th century; Mungo Park's transfer of two cities of Segou to the left bank of the Niger; careless use of a source on the history of the ethnogenesis of the Bambara and their migration to Segou; the "disappearance" of the Dogon village of Kani Na. Mungo Park's inaccuracy regarding the cities on the left bank of the Niger is not of fundamental importance for understanding the history of Mali. That cannot be said about the confusion with coordinates, since the answer to the question of whether Koumbi Saleh corresponds to the "city of Ghana" of medieval Arabic geographers largely depends on it: the coordinates of settlements in West Africa according to Arabic geographers are so inaccurate that they are impossible to use. There is, however, one partial exception: both al-Khwarizmi and al-Biruni consistently place the city of Gao significantly south of the city of Ghana, whereas in fact Koumbi Sale is located slightly south of Gao. This is an additional indirect argument in favor of the discrepancy between the "city of Ghana" and Koumbi Saleh. Of no small importance for understanding the ethnogenesis of the state-forming ethnic group of Mali, the Bambara, is the establishment of the exact direction of their migration from the "Country of Toron", the location of which has changed from east to southwest over the past century. Throughout the past century, references to certain oral traditions have constantly surfaced in literature, according to which the ancestors of the Bambara people lived southwest of Segou in "Toron", a locality that was one lunar transition from Segou. But the first mention of Toron clearly indicates that the Bambara moved from east to west. The "disappearance" of the village of Kani Na in the Bankas region of the modern Republic of Mali is one of the most striking examples of inaccuracies based on simple carelessness.