Original: Ancient Romans such as Pliny (N.H. 5.10) thought that the river near Timbuktu was part of the Nile River, a belief also held by Ibn Battuta, while early European explorers thought that it flowed west and joined the Senegal River.
Simplified: Ancient Romans thought that the river near Timbuktu was part of the Nile River and Ibn Battuta had the same opinion.