The Founding Fathers met in Pennsylvania for the original Continental Congress and The Declaration of Independence and the Constitution were drafted there. The Battle of Gettysburg was the turning point of the American Civil War and the Gettysburg Address, delivered on the battlefield is one of the best remembered speeches delivered by a U.S. president. Later, Pennsylvania was home to the first oil boom in the United States.
Today, Hershey Park and Steeler's games may be popular for visitors but the battle fields of the state, and Independence Hall and the Liberty Bell are well maintained for historical tourism.
If you're planning a trip to Philadelphia, check out Matador's guides to good eats, murals, and the Magic Garden.