That much is recorded. Beyond the bare fact of its existence and classification as a monument, the details of its construction, its working life, and its current condition remain officially undocumented in any publicly accessible form. Mills were once a central feature of the Irish rural landscape, ranging from small horizontal-wheeled structures grinding grain for a single townland to larger vertical-wheel operations serving a wider district, and Cavan's network of rivers and loughs made it particularly well suited to water-powered industry. Which kind of mill stood at Drumsillagh, who built it, and when it fell silent are questions the public record does not yet answer.

This is not unusual in itself. Ireland has hundreds of recorded mill sites, many of them noted only as map references or placename survivals, their physical remains anything from a substantial stone shell to a slight earthen hollow. The act of listing such a site is often the beginning of research rather than its conclusion, a marker placed in the landscape to indicate that something was once here, worth knowing about even before the full story can be told. Drumsillagh, a quiet Cavan townland, holds its mill in that provisional category for now, named but not yet narrated.