Terra (Latin, literally "earth"), is the name which this wiki will use for the Deverry Cycle's analogue of the "real" world. It is never named as such in the text, and is only referred to as "A Far Country." Terra exists on a different metaphysical plane from Annwn, the primary setting of the Deverry Cycle, and magical means are needed to travel between them.
Terra is the ancestral Homeland of the Deverrian and Bardel people. Their ancestors, a Celtic tribe called the Devetti, emigrated from their home of Devettia Riga in nourthern Gaul during the first century BCE in order to escape rule by the Romans (called Rhwmannees in the text).
The ancestors of the Bardekians also originally came from Terra, but are of Moorish ancestry. The books do not explain either when or for what reason they choose to make the journey to Annwn.