Following a review of the historiographic literature which attempts to explain how the important body of Arab graffiti on the bridge of Alcántara (Cáceres) could have been forgotten since its discovery in the mid-19th century, this article focuses on the most important known inscription. Much of the analysis is devoted to proving the authenticity of the warlike episode that it narrates, backed up by numismatic and documentary sources. Two particularly important elements examined in that process are the role of Prince ˓abbādíal-Mu˓tadd and the implications of the laqab with which he is cited. In a word, in both form and substance this article is of great interest as a source of historical information on the period and undoubtedly constitutes an advance in the currently ongoing study of the rest of this body of epigraphs.