In 1910, Mehmed Ziya, an Ottoman Muslim educator and an intellectual active on a number of heritage-related initiatives of his time, published an illustrated book on the Kariye mosque (Chora monastery) in Istanbul. This 70-page long publication is largely an art historical account, and provides useful documentation (also by means of photography) on the state of this Byzantine monument at that time. More than a purely art historical treatise, however, “Kaʻriye Cami-i Şerifi” is a testimony to an Ottoman Muslim interest in safeguarding the Byzantine heritage of the Ottoman capital. In this book, one finds information on what galvanised Mehmed Ziya to study this monument, and on his efforts to raise awareness, inter alia, among his students by organising a group school visit to it. Also, uncomfortable at the thought of Ottoman destruction of Byzantine monuments at the time of the conquest of Constantinople (1453), he shares his own understanding on that matter. At the end of the book, Mehmed Ziya has added copies of (a) his letter on the Chora monastery to Halil Bey, Director of the Imperial Museum, and (b) a letter by his students requesting the protection of this monument. Overall, Mehmet Ziya’s “Kaʻriye Cami-i Şerifi” is a window into the Ottoman Muslim reception of Byzantine heritage in the final decades of the Ottoman Empire. Studied in conjunction with other material, such as the views of other Ottoman Muslim intellectuals on the material remains of the Byzantine past in the Ottoman capital, it allows for an in-depth discussion of the ideology that supported such an interest, as well as the demands that accompanied it. Given that “Kaʻriye Cami-i Şerifi” remains to this day seriously understudied, a contextualized critical analysis of its content shall much enrich our understanding of Ottoman Muslim elite concerns on the Byzantine heritage of Istanbul. Besides that, at a time when emblematic Byzantine churches in Turkey are being (re)converted into mosques (largely in the name of Ottoman history), Mehmed Ziya’s book on Chora monastery/Kariye mosque may also be read as an alternative approach to Byzantine heritage from Ottoman times themselves.