Western Nile (Senegal-Niger River) according to Muhammad al-Idrisi (1154)Drawing from Classical legend and Arab sources, the "River of Gold" found its way into European maps in the 14th century. In the Hereford Mappa Mundi (c.1300), there is a river labelled "Nilus Fluvius" drawn parallel to the coast of Africa, albeit without communication with Atlantic (it ends in a lake). It depicts some giant ants digging up gold dust from its sands, with the note "Hic grandes formice auream serican arenas". In the mappa mundi made by Pietro Vesconte for the c.1320 atlas of Marino Sanuto, there is an unnamed river stemming from the African interior and opening in the Atlantic ocean. The 1351 Medici-Laurentian Atlas shows both the Egyptian Nile and the western Nile stemming from the same internal mountain range, with the note that "Ilic coligitur aureaum". The portolan chart of Giovanni da Carignano (1310s-20s) has the river with the label, iste fluuis exit de nilo ubi multum aurum repperitur.
In the more accurately-drawn portolan charts, starting with the 1367 chart of Domenico and Francesco Pizzigano and carried on in the 1375 Catalan Atlas, the 1413 chart of Mecia de Viladestes, etc. the "River of Gold" is depicted (if only speculatively), draining into the Atlantic Ocean somewhere just south of Cape Bojador. The legend of Cape Bojador as a terrifying obstacle, the 'cape of no return' to European sailors, emerged around the same time (possibly encouraged by Trans-Saharan traders who did not want to see their land route sidestepped by sea).
The river is frequently depicted with a great river island midway, the "Island of Gold", first mentioned by al-Masudi, and famously called "Wangara" by al-Idrisi and "Palolus" in the 1367 Pizzigani brothers chart. It is conjectured that this riverine "island" is in fact just the Bambuk-Buré goldfield district, which is practically surrounded on all sides by rivers - the Senegal river to the north, the Falémé River to the west, the Bakhoy to the east and the Niger and Tinkisso to the south.
Course of the "River of Gold" (Senegal-Niger) in the 1413 portolan chart of Mecia de Viladestes.
The 1413 portolan chart of Mecia de Viladestes gives perhaps the most detailed depiction of the early state of European knowledge about the Senegal River prior to the 1440s. Viladestes labels it "River of Gold" ("riu del or") and locates it a considerable distance south of Cape Bojador (buyeter) - indeed, south of a mysterious "cap de abach" (possibly Cape Timris). There are extensive notes about the plentifulness of ivory and gold in the area, including a note that reads
"This river is called Wad al-Nil and also is called the River of Gold, for one can here obtain the gold of Palolus. And know that the greater part of those that live here occupy themselves collecting gold on the shores of the river which, at its mouth, is a league wide, and deep enough for the largest ship of the world."
The galley of Jaume Ferrer is depicted off the coast on the left, with a quick note about his 1346 voyage. The golden round island at the mouth of the Senegal River is the indication (customary on portolan charts) of river mouth bars or islands - in this case, probably a reference to the Langue de Barbarie or the island of Saint-Louis). The first town, by the mouth of the Senegal, is called "isingan" (arguably the etymological source of the term "Senegal"). East of that, the Senegal forms a riverine island called "insula de bronch" (Île à Morfil). By its shores lies the city of "tocoror" (Takrur). Above it is a depiction of the Almoravid general Abu Bakr ibn Umar ("Rex Bubecar") on a camel. Further east, along the river, is the seated emperor (mansa) of Mali ("Rex Musa Meli", prob. Mansa Musa), holding a gold nugget. His capital, "civitat musa meli" is shown on the shores of the river, and the range of Emperor of Mali's sway is suggested by all the black banners (an inscription notes "This lord of the blacks is called Musa Melli, Lord of Guinea, the greatest noble lord of these parts for the abundance of the gold which is collected in his lands". Curiously, there is a defiant gold-bannered town south of the river, labelled "tegezeut" (probably the Ta'adjast of al-Idrisi), and might be an ichoate reference to Djenné.
East of Mali, the river forms a lake or "Island of Gold" shown here studded with river-washed gold nuggets (this is what the Pizzigani brothers called the island of "Palolus", and most commentators take to indicate the Bambuk-Buré goldfields). It is connected by many streams to the southerly "mountains of gold" (labelled "montanies del lor", the Futa Djallon/Bambouk Mountains and Loma Mountains of Sierra Leone). It is evident the Senegal river morphs east, unbroken, into the Niger River - the cities of "tenbuch" (Timbuktu), "geugeu" (Gao) and "mayna" (Niamey? or a misplaced Niani?) are denoted along the same single river. South of them (barely visible) are what seem like the towns of Kukiya (on the eastern shore of the Island of Gold), and east of that, probably Sokoto (called "Zogde" in the Catalan Atlas) and much further southeast, probably Kano.
North of the Senegal-Niger are the various oases and stations of the trans-Saharan route ("Tutega" = Tijigja, "Anzica" = In-Zize, "Tegaza" = Taghaza, etc.) towards the Mediterranean coast. There is an unlabeled depiction of a black African man on a camel traveling from "Uuegar" (prob. Hoggar) to the town of "Organa" ("ciutat organa", variously identified as Kanem or Ouargla or possibly even a misplaced depiction of Ghana - long defunct, but, on the other hand, contemporaneous with the depicted Abu Bakr). Nearby sits its Arab-looking king ("Rex Organa") holding a scimitar. The River of Gold is sourced at a circular island, what seem like the Mountains of the Moon (albeit unlabeled here). From this same source also flows north the White Nile towards Egypt, which forms the frontier between the Muslim "king of Nubia" ("Rex Onubia", his range depicted by crescent-on-gold banners) and the Christian Prester John ("Preste Joha"), i.e. the emperor of Ethiopia in the garb of a Christian bishop (coincidentally, this is the first visual depiction of Prester John on a portolan chart).
