I first read Bunyan's masterpiece in college. It was lost on my youth. Being groomed by some thoughtful literature professors who had an allergic reaction to allegory I found the book dull on every level. I thought it was trite, preachy, simplistic, and I didn't connect with it on an emotional level.
I picked up the book again because of a nagging suspicion that it was me, not Bunyan that failed in our first meeting. I'm so glad I did.