Hardin Run is a long 2nd order tributary to the Ohio River in Hancock County, West Virginia. This is the only stream of this name in the United States.
According to the Geographic Names Information System, it has also been known historically as:
Hardin Run rises about southeast of New Manchester, West Virginia, in Hancock County and then flows generally west-southwest to join the Ohio River at New Cumberland.
Hardin Run drains of area, receives about of precipitation, has a wetness index of 298.97, and is about 73% forested.