Tartessos (Spanish: Tartesos) is, as defined by archaeological discoveries, a historical civilization settled in the southern Iberian Peninsula from about the late Bronze Age until the 5th century BC. It had a writing system, identified as Tartessian, that includes some 97 inscriptions in a Tartessian language which has been proposed by Teresa Júdice Gamito to be a Celtic language. Tartessos was the first "entity located in southwestern Iberia to be recognised as a kingdom".
In the historical records, Tartessos (Ancient Greek: Ταρτησσός) appears as a semi-mythical or legendary harbor city and the surrounding culture on the south coast of the Iberian Peninsula (in modern Andalusia, Spain), at the mouth of the Guadalquivir. It appears in sources from Greece and the Near East starting during the first millennium BC. Herodotus, for example, describes it as beyond the Pillars of Hercules. Roman authors tend to echo the earlier Greek sources, but from around the end of the millennium there are indications that the name Tartessos had fallen out of use and the city may have been lost to flooding, although several authors attempt to identify it with cities of other names in the area.