The Miskatonic River is a fictional New England river in the works of sci-fi/horror writer H. P. Lovecraft. It is also the name of a river system called the Miskatonic Valley. The equally fictitious Miskatonic University in Arkham is named after this river. The Miskatonic was first mentioned (as "Miskatonic Valley") in the 1920 Lovecraft short story "The Picture in the House" (1920).
The fictional communities of Arkham and Dunwich within the American state of Massachusetts are said to be located along the Miskatonic. In "The Colour Out of Space" (1927), the narrator claims that there is a "small island in the Miskatonic where The Devil held court beside a curious stone altar older than the Indians."
The Miskatonic seems to follow a west-to-east path across Massachusetts, originating from springs in the hills west of Dunwich. It runs eastward past Dunwich, turns southeast, and flows through Arkham. The river empties into the sea two miles to the south near Kingsport, which lies just to the northeast.
Later writers of Lovecraftian horror, especially those building on his Cthulhu Mythos, have described the area surrounding the Miskatonic Valley and its outflow as Lovecraft Country.
The 1998 interactive fiction video game Anchorhead by Michael Gentry mentions a river called the "Miskaton River", an obvious allusion to the Miskatonic River. It flows through the game's main location, Anchorhead, to the east into the Atlantic Ocean. It is crossed by railroad tracks from a paper mill some miles outside of town to the northwest. Whateley Bridge crosses the Miskaton north of the town square. Anchorhead's university is called "Miskaton University".
Lovecraft concocted the word Miskatonic from a mixture of root words from the Algonquian language. Place-names based on the Algonquian languages are still found throughout New England. Anthony Pearsall believes that Lovecraft based the name on the Housatonic River which extends from the Long Island Sound through the Berkshires of Western Massachusetts and western Connecticut.
Daniel Harms suggests that Miskatonic is derived from the Misqat, a tribe descended from the Native Americans of Massachusetts.
It was also thought to make reference to the Merrimack River, which runs by real-life Newburyport, a location mentioned often by Lovecraft.