Seek knowledge unto the grave! Seek as far as China or even America?
Abubakari II was a prince of the Mali Empire, the successor of Mohammed ibn Gao and predecessor of Kankan Musa I. Abubakari II appears to have abdicated his throne in order to explore "the limits of the ocean"; however, his expedition never returned. Malian scholar Gaoussou Diawara has argued that he reached the Americas some time in the early 14th century, but these claims have not been widely accepted.
BBC article on Abubakari II and the debate amongst academia over his travels to the Americas prior to Christopher Columbus.
Who Came Before Columbus? By Hisham Aidi
A grandson of a daughter of the great ruler Sundiata (reigned 1230-1255), the founder of the Keita dynasty, Mansa (emperor) Abubakari became ruler of Mali in 1300. His younger half brother was Kankan Musa, who later became the famous Mansa Musa. As ruler of one of the largest empires in the world at that time, Abubakari sought to increase the power and influence of Mali even further. While his brother was interested in extending the borders of the empire to the east, toward Cairo, Abubakari apparently focused on westward expansion by exploring the waters to the west of his kingdom. Unlike most medieval Europeans, Muslim geographers such as Abu Zaid, al-Masudi, al-Idrisi, al-Istakhri, and Albufeda had concluded that the Atlantic Ocean was not the western edge of the world, and their ideas may have come to Abubakari through scholars at the great Muslim university in Timbuktu.
According to oral tradition, Abubakari gathered shipbuilders and watermen from all over his empire. He is said to have had different boat designs built so that if one failed, another might succeed. Al-Umari recorded the story Mansa Musa told in Egypt in 1324:
The monarch who preceded me would not believe that it was impossible to discover the limits of the neighboring sea. He wished to know. He persisted in his plan. He caused the equipping of two hundred ships and filled them with men, and of each such number that were filled with gold, water, and food for two years. He said to the commanders: Do not return until you have reached the end of the ocean, or when you have exhausted your food and water.
According to al-Umari, only one ship returned. Its captain reported to Abubakari that he had watched as the other ships sailed on, entered a broad current in the midst of the ocean, and disappeared. Instead of following them, he turned around and returned home.
Abubakari then decided to build a fleet of two thousand boats and to command it himself. He conferred power on Musa, specifying that if he did not return after a reasonable amount of time, Musa should inherit the throne. In 1311 Abubakari set out with his fleet down the Senegal River and headed west in the Atlantic. He never returned to Mali, and his brother became Mansa Musa in 1312.