The River Styx was a location in Dante's Inferno. It comprised most of the Fifth Circle. Those damned for the sin of Anger are immersed in a toxic and black liquid that made the river up. The angry actively fought one another above the waters, attempting to tear one another apart while the sullen laid at the bottom, unable and unwilling to remain above the water. The unwary travelers are dragged under by the angry shades. Dante's only way across was the guardian of the Styx named Phlegyas. Beyond the Styx were the gates to the City of Dis. The Tower of Anger was also located at the banks of this river that was used for signaling the boatman.
- In Greek mythology, the River Styx (Meaning "Hateful") was one of the five rivers of the Underworld. It became the most famous of the five and sometimes became synonymous with "The River of Hell". Unlike the Acheron, the Styx had no ferryman. Charon, the ferryman of the Acheron, is often mistakenly placed at the Styx in some popular media.
- In the original myths, the Styx was named after it's resident nymph who saved Zeus from destruction during the Titanomachy. In honor of Styx, he declared that her river would be the sacred river on which the holy oaths would be sworn. If these oaths were ever broken by a mortal, that mortal would instantly die. If a god broke their oath, they would be placed into a deathlike coma for several months and be maligned upon awakening for breaking their word. Furthermore, as it was shown in the myth of Achilles, it would seem that a mortal who was bathed in the Styx would be physically invulnerable to any weapons wherever their skin was directly touched by the waters (Though as Achilles had been dipped in as an infant by his mother who was another nymph, it is unknown if simply bathing in the Styx is all of that is needed to make a human invulnerable).
- In "The Inferno," Dante describes how the River Styx made much of the fifth circle up and within it's swampy waters, the souls of both the Wrathful and the Sullen were punished.
- Apparently, the Styx is so deep that Phlegyas wades underwater and only the flat top of his crown can be seen.
- Charon's severed head can be found in the Styx marsh, acting as a nest for the Pests.