This is a lightly revised version of a doctoral dissertation supervised by the editor of the series in which it now appears, and submitted at the University of Wales, Lampeter, in 2007. It is a study of the description of Jerusalem attributed to the Anglo-Saxon monk Willibald who visited it four times during his stay in the Holy Land in 724–6. As the first monograph on this topic, it is extremely welcome. It consists of five main sections, where the first provides a brief introduction to the Vita Willibaldi itself and the other main sources for the topography of Jerusalem until the Crusader period, the second provides the contextual background, describing the life of Willibald, his travels in the Holy Land and the history of Jerusalem itself until the early eighth century, the third analyses Willibald's alleged descriptions of eight main sites in or about Jerusalem, the fourth discusses Willibald's image of Jerusalem, and the fifth summarises the main findings in a brief conclusion. Unfortunately, while Aist sometimes has interesting comments to make about the descriptions of individual sites, his work fails to persuade as a whole because of his uncritical attitude towards his sources. There are two main sources for the topography of Jerusalem during the Umayyad period, the Vita Willibaldi which the nun Hugeburc composed sometime shortly after Willibald had dictated an account of his travels to her in 778, and the De locis sanctis which Adomnán of Iona (d. 704) composed sometime after an otherwise unknown bishop Arculf had dictated an account of his travels to him, or so he claimed. Unfortunately, Aist treats both texts as if they are inerrant, as if Hugeburc and Adomnán were the perfect recorders of the perfect memories of two men who really did visit the Holy Land. As I have demonstrated elsewhere, major problems in the De locis sanctis point to the conclusion that Adomnán composed it on the basis of written materials gathered by someone who need not have proceeded any further than Constantinople, where none of these materials need have described anything dating later than c. 640 (Ériu lii [2002]; ARAM xviii–xix [2006–7]). Aist is aware of the problems, but ignores them. He does the same in the case of similar problems in the Vita Willibaldi, where he fails to draw the necessary conclusions from gross contradictions between this and other texts in the description of several key monuments. For example, he refuses to admit that either Hugeburc, or her source Willibald, has confused a description of the large column at the North Gate with a Marian monument consisting of four smaller columns at the East Gate (pp. 166–74). Elsewhere, he sees no real problem in quite literally squaring a circle (pp. 208–9), forcing two different descriptions of the bronze railings at the heart of the Church of the Ascension to describe the same railings rather than admit the obvious, that their authors, Hugeburc and Adomnán, cannot be describing this monument at the same period. In conclusion, therefore, one still awaits a truly critical reading of the Vita Willibaldi.