1. On February 15, 1791, the Commonwealth of Pennsylvania established the first state-supported prison in the United States, the Eastern State Penitentiary. This prison was known for its unique form of punishment, called the Pennsylvania System, which emphasized solitary confinement and rehabilitation rather than retribution.

2. In 1861, on February 15, William Henry Johnson became the first African-American to receive the Medal of Honor for his bravery during the Civil War. Johnson, who served in the Union Army, was a member of the 38th Regiment of the United States Colored Troops and his valor in battle helped inspire other African-Americans to enlist in the military.

3. On February 15, 1839, the Susquehanna River froze in central Pennsylvania during a particularly brutal winter. This allowed for an unusual winter crossing of the river, which was typically only navigable by boat. In fact, the frozen river was so thick that people set up shops and even homes on the ice.

4. February 15, 1952, marked the premiere of the groundbreaking television program "American Bandstand," which was filmed in Philadelphia and hosted by Dick Clark. The show featured live musical performances and interviews with popular artists and helped launch many careers in the music industry.

5. On February 15, 2003, a massive snowstorm hit the eastern United States, dumping up to two feet of snow on parts of Pennsylvania. This storm, known as the Presidents' Day Storm of 2003, caused widespread power outages and travel disruptions and resulted in several fatalities.