An early pioneer in aviation and clearly seeking an adrenaline rush, Abbas Ibn Firnas, a 9th century inventor living in Cordoba, Spain, built a homemade glider and launched himself from a tower in the then-Moorish city. His flight was largely successful, in that he glided briefly over Cordoba before taking a hard landing that left him with an injured back.
Still, though, accounts of Ibn Firnas' short flight were well documented and, as a result, word of the feat spread. As professor Salim al-Hassani, Chairman of the Foundation for Science, Technology and Civilisation, told CNN in 2010, Ibn Firnas' glider design even inspired Leonardo da Vinci centuries later.
His flight allegedly inspired another unlikely daredevil in the 11th century, a monk known as Eilmer of Malmesbury (illustrated here), who jumped off the summit of a tower on Wiltshire Abbey and glided a distance of two football fields. Historic accounts of the connections between the two flights are sketchy, but it's plausible that Crusaders could have brought news of Ibn Firnas' attempt back home with them.