"Situation - The parish and barony is a part of the county of Stirling, although it happens to be totally disjoined from every part of it. No certain account can be given, how this has happened. It is surrounded by the shire of Clackmannan on the east, south and west, and on the north, it is bounded by a part of the county of Perth. It extends in length, from east to west, somewhat more than two miles and a half; and from south to north, rather more than four miles."
Parish of Alva (County of Stirling) by the Rev. Mr. John Duncan (Statistical Account of Scotland 1791-1799)
An adjustment was made by the Boundary Commission in 1891. Previously the county (Clackmannanshire) contained four parishes: Alloa, Clackmannan, Dollar and Tillicoultry and portions of Logie and Stirling. The Clackmannanshire portion of Stirling parish was transferred to Stirlingshire. The Clackmannan portion of Logie parish was divided into three parts. One was transferred to the Stirlingshire parish of Logie; a second was united with the parish of Alva, which was wholly given to Clackmannanshire; while the third part was absorbed by the parish of Alloa.
[Clackmannan and Kinross by J.P.Day B.A. B Sc., 1915 ]
See also GENUKI Clackmannanshire for more on Alva.