Transforming a Screenplay into a Novel

Work begins on transforming one of my screenplays into a novel. The Holy Lance, as it's currently styled, begins in a cathedral in the holy city of Echmiadzin, Armenia, in 1099 A.D. The script says simply "EXT. CATHEDRAL - NIGHT" and, to orient the audience, "SUPER: THE HOLY CITY OF ECHMIADZIN, ARMENIA, 1099 A.D." That's it. Obviously, a reader, as opposed to a director, needs more. So, more it is. Those first two script directions have been transformed into the paragraph below, which, in my view, is a solid start to this process.

"By the year 1099 A.D. the cathedral was already ancient. Few of its worshipers could, if they cared to, accurately name the year construction began on it, or the year, nearly a century later, the cathedral was deemed complete. The names of the carpenters, stonemasons, and glaziers who labored on the massive project for generations were long forgotten by the end of the first century of the second millennium.  Even the repairs undertaken after the earthquake of 893 A.D. had, two centuries later, blended in with the original structure so thoroughly that only the most discerning eye could detect them. It is the fair to say that in the 11th century few who lived in that region of the plain of Ararat drained by the Kasagh River could have told a curious visitor much about the cathedral’s already lengthy history. What nearly all who lived in that region could have told that same visitor is that the cathedral was a massive vault standing guard over one of Christianity’s most powerful relics; that hidden deep within the cathedral’s bowels, accessible via a complex system of narrow tunnels, was a small chapel with a stone altar adorned by a plain wooden cross and a long, rectangular iron box with three leather hinges and three gold clasps; and that in the iron box, on a bed of the purest white silk, lay the spear that a lone Roman soldier, standing on the skull-shaped hill of Golgotha, plunged into the side of the Son of God."