There are so many things to do see in the heart of Gettysburg from museums, battlefields, ghost tours...https://gettysburgghosts.com/ Pennsylvania is also home to the Pennsylvania dutch known for their food and crafts - good stop for holiday gifts LoL Pennsylvania is big so Pittsburgh is about 3.5 hours west of Gettysburg while Philadelphia is about 3 hours East and closer to New Jersey.
Baltimore is even closer if you want to see the Inner Harbor, Chesapeake Bay, or visit my favorite spot, The National Aquarium! Edgar Allan Poe is a celebrity here, along with a mountain of other authors and poets. The George Peabody Library, shown in the photo above, and the Walters Art Museum are only a few of the odes to Baltimore's love of books that you could check out.