Periplus (book)

A periplus (plural: peripli) is a manuscript document that lists ports and coastal landmarks, in order and with approximate intervening distances, that the captain of a vessel could expect to find along a shore. In essence, it is a pilot's guide or route instruction manual for navigating coastal waters. The term derives from the Greek word "periplous" (περιπλοῦς), meaning "sailing-around."

Peripli served a critical function in ancient maritime trade and exploration, offering practical information about anchorages, water sources, trading opportunities, local populations, and potential dangers such as shoals or hostile inhabitants. While not always strictly accurate or comprehensive by modern standards, they provide invaluable insights into the geographical knowledge and navigational practices of the time.

Many surviving peripli are anonymous, making it difficult to ascertain their authors, dates of composition, and intended audiences. However, some notable examples exist with attributed authorship or clearer historical context. These documents represent a vital source of information for historians, archaeologists, and maritime scholars studying ancient trade routes, seafaring techniques, and geographical understanding. The contents of a periplus can vary considerably, ranging from brief lists of coastal features to more detailed descriptions of settlements, customs, and resources.