Then, something I hadn't seen before, the whole procession began to make its way around the entire basilica, from "top" to "bottom" and back up around the other side of the papal altar, chanting a Litany the whole while (I couldn't quite figure it out, maybe the Marian one?) and with all of us coming too! Here is a view of it from the far end of the basilica, near the main doors, with the lead procession on the right and all the faithful following along behind and around.