The inspiration for the workshop that led to this volume came from a realization that in the context of the Crusades in particular, but also of medieval warfare in general, most historians have written about military campaigns as though they took place in a geographical, meteorological, and oceanographic vacuum. In most books military forces move from one place to another without the slightest difficulty. Actual routes followed, if discussed at all, are almost never done so from the perspective of trying to understand why they were chosen from a logistical point of view, sometimes from a tactical point of view but almost never from a logistical one. Naval forces are given even less consideration. They leave the West and arrive in the Holy Land as though their commanders had merely engaged the engines on their cruise ships and set course for the Holy Land by the shortest possible route. Almost any book about the Crusades showing the supposed routes of those who came by sea will demonstrate this lack of appreciation of the technological and geographical realities of the Middle Ages. In fact far more attention has been paid to logistical infrastructures, primarily military rather than naval, by ancient historians. Some ancient sources are more informative than most medieval ones and it will have become apparent to anyone reading this book that most contributors have utilized the research of ancient historians considerably. A cursory glance at the Consolidated Bibliography will reveal just how few publications have been devoted to the logistics of medieval military campaigns.