The Bedfordshire Historic Environment Record [HER] contains information on the county's historic buildings and landscapes and summaries of each entry can now be found online as part of the Heritage Gateway website. The entry [HER 1850] for Hollington Mill, a watermill standing on the River Flitt near Hollington Bridge states: "The site of a mill. A building on the site is called The Old Mill House on a map of 1826, and this has been identified with the Barley Mill mentioned several times in the Dunstable Cartulary. The mill was granted to Dunstable Priory about 1240. It is also mentioned in deeds dating from 1596 [sic] and 1649, where it is described as "two mills under one roof". It is not known when the mill ceased to operate, or when the building was demolished".
There is no mention of a mill at Flitton in the Domesday Book of 1086. The earliest mention is made in the Cartulary of Dunstable Priory, translated and published by Bedfordshire Historical Record Society as their Volume 10 in 1926. About 1200 William de Flitton granted to the priory "the barley mill which Hubert formerly held from William his [Hubert's] brother the lord of Flitton, together with the mill-pond and fishery of the pond, and common of the upper water where other freemen may fish; with land of the Lide [on Old English word for a slope]; with a holm next the meadow of John de Wadelowe; with the right of cutting turves in the marsh to repair the dam; and with common in the marsh". William's son Philip confirmed the grant between 1220 and 1245
In March 1597 Francis Morgan was to marry Judith Duncombe and a marriage settlement between them saw Hollington Mills, as well as a windmill in the same parish and some other land, all occupied by Morgan's father John, conveyed to trustees as a jointure for Judith [L5/374].
In 1649 Edmund Morgan, probably the son of Francis and Judith, mortgaged two water mills under one roof called Hollington Mills and six acres of nearby land to Thomas Richardson of Ampthill for £30 [L5/375]. The reference to two mills under one roof refers to two pairs of mill stones. Morgan took a further advance of £20 in 1652 [L5/376] and £48/10/- in 1654 [L5/377]. This mortgage and further advances was assigned to William Hopkins of Flitton in 1658 [L5/378].
In 1660 Morgan and his brother Francis conveyed the mills to William Daniell, Lord of the Manor of Newbury, Silsoe for £300, still subject to mortgage debts totalling £140 [L5/380]. A rental of Newbury Manor of 1681 includes the mills and closes, now occupied by Andrew How at a rent of £18 per annum [L5/395]. This manor was acquired by Marchioness Grey in 1775 [L5/411-412] and remained part of the Wrest Park Estate until a succession of Law of Property Acts in the 1920s extinguished all manorial incidents, courts and copyhold tenure of land. This effectively abolished manors in all but name.
As noted by the Historic Environment Record it is not known when Hollington Mills ceased to operate but it was a probably before 1839 as the Pigot & Company's directory for this year, and all subsequent directories, make no mention of a mill in Flitton, though the mill at Greenfield is constantly mentioned.