The Santa Croce church in Andria (Bari, Italy) preserves an unknown fifteenth-century mural cycle with the Legend of the True Cross. The cycle contributes to the dissemination of the theme in Europe, and outside Tuscany in particular. Moreover the program in the grotto–church contributes to the cult and the perception of the Legend of the True Cross in a Mediterranean and eremitical context, revealing an important mediating role of the Byzantine East. In short, this article analyses the cycle of Andria in its iconographic tradition and the specific syncretic models between East and West, and, finally, contextualizes this Legend of the True Cross in the so-called civiltà rupestre.