The title is rendered confusedly in the citation, so that you have to look at the cover to see that it's actually Travel and Travelers OF THE Middle Ages.
I knew a lot of the stuff about travel throughout 'Christendom'. This book added a lot about Arabic travellers, and some (not as much as other sources about Viking explorations of places like the Atlantic, as well as unexpected things like Viking incursions into Russia (in German, 'Russland'--the land of the redheads). There are other sources on many of these sources, but this is a good introduction.
There should be companion editions, for example one about the Chinese Black Fleet (though that was toward the end of the Middle Ages), and also some idea of travel and trade in North & South America, during (for example) Hopewell times. But if I were assigned to teach a course on 'pre-Columbian' travel of the 'post-Classical' period, I'd probably use this book as an introductory text.
A useful depiction of travel in the Islamic world, correcting the misapprehension that travel was severely restricted at the time (It was in Christendom, maybe, but not necessarily elsewhere).