
Catwalk on the outside of the bridge at Oxford station
What is the catwalk on the side of the bridge over Oxford station?
My thoughts
It could be a platform from which a man in a harness could clean the bridge. But the gap in the handrail is on the front, not the side (and the bridge clearly hasn't been cleaned yet this millennium).
It could be to allow workmen on top of trains. But the gap in the handrail is positioned between tracks.
It could be a platform on which a ladder can be placed to allow work on top of the bridge. So why is there a gap in the handrail at all?