If you go to the latest Halo Anniversary feature issue of OXM, the bottom right of the first page has this weird map. I don’t think I recognize an area like it from the campaign.
Speculation? For those that haven’t seen the map, it’s this sort of sandy area with a large base of sorts. Yes I know I make terrible descriptions, but I don’t suppose that I’m allowed to post videos of the leaked OXM scans here.