It's dated but here's an article I wrote on the blog about Harper's Ferry. It's one of my favorite places although I have not been down there in a couple years.
I never fished there, but stopped by one time to see the historical town. The river looked very nice there. Lots of good habitat, in a scenic setting. I don't think you need a guide. You could just wade fish, as shown in Dave's painting.
Very neat little town. Besides the historic sites, she really liked the little shops.
Nearby Antietam is very interesting too.
I enjoyed it almost as much as Gettysburg.
I didn't fish.
But saw many people floating down the Potomac in large rubber tubes.
If the weather stays hot like it is now, sure be a nice way to spend the afternoon too.