Jerusalem - earthly and heavenly, past, present and future - has always informed the Christian imagination: it is the intersection of the divine and human worlds, of time and eternity. Since the fourth century, it has been the site of the round Church of the Holy Sepulchre, built over the empty tomb acknowledged by Constantine as the tomb of Christ. Nearly four hundred years later, the Sepulchre's rotunda was rivalled by the octagon of the Dome of...