The Qartheen language is spoken in the ancient port city of Qarth. It is known that the Qartheen have their own language because when Daenerys Targaryen leaves the city's walls, she is glad "to hear men speaking Valyrian once more, and even the common tongue." However, that remains the only reference to the existence of this language, so we know nothing about its history, sounds, or structure, other than what can be surmised from the names of Qartheen people and places.