How are you going to get back?
A 200 mile loop is a pretty impressive thing. I think you'd be surprised what is 100 miles away from Harrisburg. Not trying to talk you out of your route, I take a similar approach with my fleche route, it goes 226 miles pretty much due east of here. But that was in hopes of a ride with a massive tailwind the entire way
Your route is likely to have, at best, a crossing headwind the whole way.