Dark City Treno, also known as Treno; the City of Nobles, is an economically polarized city in the eastern part of the Mist Continent on Gaia. Treno has no existent middle class; instead, all of its inhabitants are either extremely wealthy or extremely poor. The rich nobles live down on the waterfront, while the poor live up in the slums around the city. Treno is known as the Dark City due to the perpetual state of darkness in which it remains.