Pleasant Run is mostly in Hamilton County, south of Fairfield. The Regular Baptist Church of Pleasant Run was formed in 1810 on the county line where John Gray Road and Winton Road intersect at the southern edge of Fairfield, according to Mrs. Esther Benzing. It is shown as the Pleasant Run Meeting House on James McBride's 1836 map. Mrs.Benzing, in her book, Fairfield, Ohio, said "the Pleasant Run area seemed to start on the Cincinnati-Hamilton Road, now Pleasant Avenue, where it leaves Symmes Corner and extends down to where New Burlington begins" [in Hamilton County]. She said "it was named for a little stream on the east line of the township adjacent to the Butler County line, now in the City of Fairfield." A Pleasant Run post office was in a general store on the southeast corner of the present intersection of U. S. 127 and Kemper Road in Hamilton County. "Pleasant Run, named for the stream, was located on the east line of (Colerain) Township, half a mile south of the Butler County line," said Ruth J. Wells in her book, Colerain Township Revisited. "An early hotel, Farmers Rest, was located here. This was on the Hamilton Turnpike," Mrs. Wells explained. "James Huston became its postmaster in 1846 with Paul Huston taking over in 1854." Mrs. Benzing said "Pleasant Run would not be Pleasant Run without the Presbyterian church" built in 1854 at U. S. 127 (Pleasant Avenue) and John Gray Road, now the site of a Wahlgreen's Drug Store. Pleasant Run, the creek, empties into the Great Miami River in the City of Fairfield, north of the area once known as Black Bottom or Fairplay. Its channel was straightened, altered and widened in several locations in the 1980s to lessen erosion and the potential for flooding.
"Pleasant Run is a stream of some size," said the 1882 county history. "It takes its head partly in Hamilton County; its current is tortuous and winding; its principal tributary, Pond Run."