Well, if you are taking all the trouble to come here from Finland to go to Carlisle, you at least have to hit up Hershey Park while you are out there. It is extremely close, and is a fun day for the whole family (rollercoasters, chocolate... what more could you ask for?
). Then, it depends on how big of a detour you are willing to take. You can drive pretty directly from Carlisle to Washington, D.C., Philadelphia, or back to NYC. DC is a great city if you want to do the whole museum/monument/government building kind of thing. Philly has a fair deal of museums (Franklin Institute, Constitution Center) and also has Independence Hall, amongst other historic landmarks. There's also the Camden Waterfront by Philly (you ONLY want to go to the waterfront, and ONLY during the day... the city isn't the most dangerous in America just by coincidence), where you can visit the Camden Aquarium and take a tour of the Battleship USS New Jersey. Since you will already have gone to NYC, I don't know if you want to go back, but there is a lot of things to do there, and you will not run out.
You are probably best off arranging to fly into NY, and out either through DC or Philly.
All that aside, I am hoping to be at Carlisle this year, and hopefully there on a day (possibly days
) when everyone else is. (If not, this time I will actually take the left-behind food. Sourdough bread, anyone?