The Sphinx Delta stretches from a few miles north of Sothis all the way to the Inner Sea. The Sphinx River breaks into many sluggish, shallow weed-choked channels and surrounds marshy islands and sandbars. The channels shift with the seasons, but there is almost always one main channel that is used by deep-draft ships; otherwise, a channel has to be dredged.
The main channels are well patrolled and charted, but the backwaters are not worth the effort. The swamps are home to ferocious beasts like hydras and basilisks. Tribes of isolationist lizardfolk live in the delta as well. The uncharted waterways of the delta are used by cults of Erastil, Gogunta, and Hanspur.