periplus

A periplus is an ancient nautical document that describes a coastwise sailing route, listing ports, landmarks, distances, currents, and hazards to aid mariners navigating along a coastline. The term comes from the Greek peri- “around” or “along” and ploús/ploûs meaning “voyage” or “sailing.”

The most famous example is the Periplus of the Erythraean Sea, a Greek travelogue from roughly the 1st century CE. Its anonymous author recites navigational guidance and commercial information for divers coastal zones from the Red Sea and the Horn of Africa to the Indian Ocean. It details prevailing monsoon winds, typical ships, and the goods exchanged at various ports, including spices, dyes, precious metals, ivory, and textiles. The text also offers ethnographic observations and glimpses of distant markets and political entities, and it serves as a key source for understanding ancient trade networks, maritime technology, and coastal geography.

In scholarly use, peripla (plural of periplus) are valued for reconstructing ancient maritime routes and port functions, even though their descriptions are brief and sometimes ambiguous. Identifications of some places and distances remain debated, requiring cross-referencing with other historical and archaeological evidence.

Beyond the Erythraean Sea, the term periplus can refer to similar coastwise navigational documents from antiquity that guided sailors along shorelines and between ports. In modern usage, the word retains its historical sense as a genre name for such itineraries and their study.