The Seti Plains were the vast central grasslands of Quon Tali and home to the Seti people. They was crossed by the ancient Trunk Road between the city of Quon Tali and Li Heng. The border between the Seti Plains and the Dal Hon Plains was somewhere south of the Idryn River. Li Heng was surrounded bu the plains, which continued for an unknown distance to the city's east.
It is unclear whether Por Seti referred to the same region. Por Seti appears on the maps of Quon Tali, seemingly in the northern region of the plains, but this term does not appear in the books. The Seti Plains are referred to throughout the books, but are not specifically named on the map.