Thanks for all of the info.
We are going to be there this Friday and are leaving on Monday morning. From what I have looked up, on Google maps, our hotel(on Broad ST) is @ 1 mile from the Franklin. @1 mile the other way is the Liberty Bell. I was hoping to park the car on Friday and walk most of the time. If there are other suggestions that require driving I am all for that too. The submarine sounds cool!
Again, thanks for all of the info and invites!