Well, I thought the DEN-PIT was long and actually got me intrigued on the DEN RJ flights until I saw the 1400 mile RJ SFO-OKC and said wow. While Term B at IAH seems to be the king of RJ liftoffs and landings, DEN has to have some of the longest RJ flights minus the one above. At times I think Term B at IAH should be it's own airport with the number of flights.