The Codex Calixtinus, the twelfth-century manuscript containing the oldest version of the so-called “Pilgrim’s Guide to St James,” has “disappeared” from a safe in the cathedral of Santiago de Compostela. Staff discovered its absence late on Tuesday but it is not clear when exactly the manuscript was stolen, if theft there is. There were no signs of forced entry, and only two people, in addition to the dean of the cathedral, have access to the manuscript. El País, which offers the most extensive coverage of the mystery that I have seen, notes that its value is “incalculable.” Like many medieval manuscripts around the world, the Codex Calixtinus is not insured.