1. In 1776, the Continental Congress in Philadelphia officially signed the Declaration of Independence, which declared the thirteen American colonies as independent states separate from British rule. This momentous occasion is celebrated every year on July 4th, but its official signing took place on August 2nd.

2. In 1858, the first oil well was discovered in Pennsylvania by Edwin L. Drake. This discovery led to a huge boom in the oil industry and established Pennsylvania as the center of the industry for many years.

3. In 1909, the Lincoln Highway was officially opened, running from New York City to San Francisco and passing through Pennsylvania. It was the first transcontinental highway in the United States and played a major role in the development of national automobile travel.

4. In 1971, the groundbreaking documentary film "Gimme Shelter" premiered in Pennsylvania. The film chronicled the Rolling Stones' 1969 tour and the tragic Altamont Speedway concert where a fan was killed by a member of the Hells Angels motorcycle gang.

5. In 2012, a massive sinkhole opened up in Bethlehem, Pennsylvania, swallowing up part of a street and several parked cars. The sinkhole was caused by a collapsed storm water drain and took several weeks to repair.