The Great Train Wreck of 1856 occurred on July 17, when two trains collided near Camp Hill, Pennsylvania. The accident involved a passenger train traveling from Philadelphia to Pittsburgh and a freight train. Due to a miscommunication about track signals, the two trains crashed head-on, resulting in a tragic loss of life. This disaster is considered one of the deadliest train accidents in American history, with approximately 60 people killed and many more injured. The wreck highlighted the need for improved safety measures in the rapidly growing railroad industry, leading to changes in signaling and communication practices.