re: What city/area is the epicenter of these interstate rivalries?

In Arkansas it’s worth noting how many LSU fans there are up here. Like I’ve had multiple teachers with LSU flags in their room or seen people walk-in around school in LSU merch. I’d say central and south arkansas lends to a lot of Arkansas-LSU rivalry

But only because Arkansas views LSU as a rival and not vice versa. I get a lot of crap for being an LSU fan in Arkansas and I can’t imagine the same for an arky in N Louisiana