'De locis sanctis' ('Concerning sacred places') was composed by the Irish monk Adomnán, a copy being presented to King Aldfrith of Northumbria in 698. It was based on an account by the Gaulish monk Arculf of his travels to the Holy Land, from which Adamnan, with aid from some further sources, was able to produce a descriptive work in three books, dealing with Jerusalem, Bethlehem, and other places in Palestine, and briefly with Alexandria and Constantinople, called De locis sanctis ("Concerning the sacred places"). It aimed to give a faithful account of what Arculf actually saw during his journey.