Ali ibn Yusuf
According to the Muslim cartographer Muhammad al-Idrisi, the "Mugharrarin" (also translated as "the adventurers") sent by Ali ibn Yusuf, led by his admiral Ahmad ibn Umar, better known under the name of Raqsh al-Auzz reached a part of the ocean covered by seaweed, identified by some as the Sargasso Sea, which stretches into the Atlantic from Bermuda.