This article deals with Hecataeus of Miletus fr. 310 Jacoby, featuring a curious list of islands located along the Nile, and bearing Greek names such as Ephesus, Chios, Lesbos, Kypros and Samos. Scholars generally assume the list, composed in the late sixth or early fifth century, represents joint Greek emporia established on Egyptian soil, thereby serving as a reliable testimony to the emergence of collective Greek identities during the late Archaic period. The composition of the list, along with the contemporary historical, cultural and archaeological contexts of its place names, is examined with particular emphasis on the collective identities of the islanders. On this basis, it is contended that the list lacks any evidence pertaining to Greek commercial footholds or collective identities in Egypt. Rather, fr. 310 serves as a practical navigational mnemonic, delineating culturally familiar geographical landmarks to assist Greek sailors in traversing a complex foreign river passage. The fragment now emerges as a valuable historical document, illuminating Greek navigational knowledge and practices during the late Archaic period.