Swiss explorer and scholar John Lewis Burckhardt (1784–1817) devoted himself to the study of Arabic language and culture, and between 1809 and 1817 he explored Syria, the Hedjaz, the Levant, and Egypt under the assumed name Sheikh Ibrahim ibn Abdallah. His journeys began with a commission from the London-based African Association to seek the source of the Niger River. Disguised as an Arab and in constant danger of discovery and betrayal, he traveled to sites forbidden to Westerners and kept a diary rich in ethnographic, cultural, geographic, and political observations. Traveling by camel and donkey as well as on foot, Burckhardt endured profound hardships, including robbery and abandonment by unscrupulous guides and periodic bouts of dysentery, which ultimately killed him at the age of 32. He was buried as a Muslim, and the tombstone bears his assumed name. His enduring achievements include being the first modern European to lay eyes on the ancient Nabataean city of Petra and among the first to describe the customs of the Hadj pilgrimage. Burckhardt's accounts assisted Sir Richard Burton in his subsequent explorations, and they retain their fascinating historic value.