1. On April 28, 1788, Pennsylvania became the second state to ratify the United States Constitution, after Delaware. This historic event established the framework for the federal government and its relationship with the states.

2. The Pennsylvania Railroad Company was incorporated on April 28, 1846. This railroad company became one of the largest corporations in the world, and played a significant role in the industrial growth of Pennsylvania and the United States.

3. The first-ever professional basketball game was played in Hershey, Pennsylvania on April 28, 1896. The game was played between the Trenton YMCA and the Brooklyn YMCA, and marked the beginning of a new era in sports.

4. April 28, 1906 marked the beginning of the San Francisco earthquake and fire, which ultimately caused widespread destruction and loss of life. While Pennsylvania was not directly affected by this event, it was one of the many states that provided aid and support to the people of California in the aftermath of this disaster.

5. On April 28, 1914, Charles W. Kutz became the first person to fly an airplane in the state of Pennsylvania. Kutz's flight took place in Allentown, and paved the way for the development of aviation in the state and beyond.