Nagnata (Greek: Νάγνατα) or Magnata (Greek: Μάγνατα) is a town noted on the co-ordinate map of the 2nd century AD Alexandrian scholar Claudius Ptolemy in the territory of the Nagnatae (Ναγνᾶται).[1] It is located in northwest Hibernia between the mouths of the rivers Ravius (Ῥαουίος), perhaps the Erne, and Libnius (Λιβνίος), perhaps the Moy.[2] This is the only town noted on the Irish west, southern or northern coast. Surviving manuscripts of Ptolemy's Geography refers to the towns Hibernis (Teamhair'Erann/Tara), Rhaeba (Cruchain/Rathcroghan) and Magnata (Sligo) as "ἐπίσημος" (episēmos), an Ancient Greek word meaning "eminent" or "distinguished". Much of his work was based on the now lost geography of Marinus of Tyre.
As there were no proper urban centres in early Ireland and as Ptolemy's information was derived indirectly through traders, it is likely that the places which he calls "cities" were ancient places of assembly and hence trade. It is the only written evidence for knowledge or contact between the northwest of Ireland and the classical world in the European Iron Age.
That Phoenician and Greek ships had reached Ireland, possibly as early as the 6th century BC, is known from a now-lost merchants' handbook: the Massaliote Periplus, describing the sea routes used by traders from Phoenicia and Tartessus in their journeys from Hispania to Britain and the "Sacred Isle" of Ireland. Evidence for earlier contact may be an Irish lunate spearhead from the 10th century BC which was found in the harbour of Huelva in southern Spain.[3]