Pennsylvania was dubbed the Keystone State because of geography: It lay between five other former colonies in the newly formed U.S. and seemed to physically lock the country together. But its nickname could equally apply to Pennsylvania's key role in the history and development of the U.S., from colonial times to the present. Appropriately, history is what draws many travelers to the state nowadays. At Valley Forge where the Continental Army weathered a tough winter and formed the fighting unit that would win the country's independence. Dont miss the tour at Gettysburg grounds where perhaps the most important battle in the nation's history was waged. Also Scranton is a must-see and gives a better understanding of the industrial capabilities that helped make the U.S. a world power. The mountains create beautiful vistas and play host to the resort playground of the Poconos and the outdoor activities of the Laurel Highlands. Philadelphia and Pittsburgh provide big-city cultural and entertainment possibilities, and rural getaways like Bucks County and the Brandywine Valley mix scenic countryside with affluent living.