Hershey's Chocolate World and Hershey Park are just 45 minutes from York! Chocolate world offers a free "factory" tour - with a free piece of chocolate at the end ;) You can also make your own chocolate bar, go to the amusement park and much more!
The Gettysburg battlefield/national park is about 45 minutes from York. You can take a driving tour around the battlefield for free, and there are a few museums and tours that you can pay for as well! The town of Gettysburg is also very cute! We ate delicious burgers at "The Gettysburger" after we went to the park after touring our venue!!
You might have heard of Sight & Sound Theater, but it's a theater that does live reenactments of Bible stories. They are truly incredible shows. If you're staying in the area, it's a little expensive but I would highly recommend going to a show!