1. In 1787, Pennsylvania ratified the U.S. Constitution, becoming the second state to do so after Delaware. This significant moment in American history laid the foundation for the federal government and the country's system of laws and democracy.

2. On June 26, 1819, the first steam locomotive in the U.S. was tested in Pennsylvania. The Stourbridge Lion was built by English engineer John B. Jervis and tested on a short stretch of track in Honesdale, Pennsylvania. The success of this test paved the way for the development of the American railroad system.

3. In 1899, the world's first trolley park, called Willow Grove Park, opened in Pennsylvania. This amusement park featured roller coasters, water rides, and other attractions, and became a popular destination for families throughout the region.

4. On June 26, 1925, the famous "Scopes Monkey Trial" began in Dayton, Tennessee. Although the trial itself took place in Tennessee, it had significant implications for Pennsylvania and the rest of the country, as it tested the constitutionality of teaching the theory of evolution in public schools.

5. In 1978, the Supreme Court of Pennsylvania ruled that the state's death penalty was unconstitutional. This decision made Pennsylvania the first state in the modern era to abolish the death penalty, and set a precedent for similar actions in other states.