Source: Planar Adventures, pg(s). 110
Shethalliahaya is the home city of the shaes on the Shadow Plane, built from black shadowstone and capped in white. Visitors are rarely allowed into the city; the rare few that are speak of arcane secrets unknown outside the city, or the occult rituals used by the shaes to shed their corporeal forms. According to the followers of Sivanah, the city is also home to one of her sacred temples. As evidence of this, Sivanah's followers point to the similarities between Sivanah's veils and the shaes' masks; as well as the Severed Mask, one of her divine servitors who is a mighty shae.