Periplus Maris Erythraei

The Periplus of the Erythraean Sea or Periplus of the Red Sea (Greek: Περίπλους τῆς Ἐρυθράς Θαλάσσης, Latin: Periplus Maris Erythraei) is a Greco-Roman periplus, written in Greek, describing navigation and trading opportunities from Roman Egyptian ports like Berenice along the coast of the Red Sea, and others along Northeast Africa and the Sindh and South western India. The text has been ascribed to different dates between the 1st and 3rd centuries CE, but a mid-1st-century date is now the most commonly accepted. While the author is unknown, it is clearly a firsthand description by someone familiar with the area and is nearly unique in providing accurate insights into what the ancient European world knew about the lands around the Indian Ocean.

The Erythraean Sea, or in modern spelling, Eritrean Sea (Greek: Ἐρυθρά Θάλασσα) is presently a Greek name for the Red Sea; to the ancient Greeks it included the Indian Ocean and the Persian Gulf.

The work consists of 66 chapters, most of them about the length of a long paragraph in English. For instance, the short Chapter 9 reads in its entirety:

In many cases, the description of places is sufficiently accurate to identify their present locations; for others, there is considerable debate. For instance, a "Rhapta" is mentioned as the farthest market down the African coast of "Azania", but there are at least five locations matching the description, ranging from Tanga to south of the Rufiji River delta. The description of the Indian coast mentions the Ganges River clearly, yet after that is somewhat garbled, describing China as a "great inland city Thina" that is a source of raw silk.

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