The triple themes of this book - migration, pilgrimage and travel in Islam - are as old as the religion itself. The Prophet Muhammad made his famous archetypal "Hijra" (migration) from Mecca to Medina in 622 AD, a year which became the Year 1 of the Muslim lunar calendar; the "Hajj" (pilgrimage) of Farewell enacted by the Prophet in 632 AD provided the paradigm for all future pilgrimages to the sacred Ka'ba in Mecca; while a much quoted hadith portrays the Founder of Islam counselling his followers that they should seek knowledge even as far as China. The concept of "Rihla" (travel) in search of knowledge thus became a primary motif in the lives of many medieval - and modern - Muslim scholars, jurists, collectors of tradition and, indeed, ordinary people. The editor is also author of "A Popular Dictionary of Islam."