Holy Austin Rock (South Staffordshire) is the only domestic rock-cut building in Britain which has been restored and opened to the public. It has been the subject of earlier investigations and the enigmatic rock-cut houses have been thought to be 18th century in origin, as this is when they were first mentioned in the historical record. This paper presents the results of a new survey and analysis of the site. As part of this study the fabric and archaeology were reinterpreted based on the current understanding of similar sites elsewhere. The paper establishes a mediaeval origin for many of the rock-cut buildings and details fragmentary but surviving diagnostic features such as inscribed crosses, medieval fireplaces, doors and moulding. Repeated later phases of re-use and abandonment of the site have confused the picture, but a much earlier origin than previously thought is demonstrated. The paper also explores the possible origin of the name Holy Austin and how this may relate to nearby sites with the same name.