1. Battle of Gettysburg ended: On July 26, 1863, the Battle of Gettysburg officially ended with a Confederate retreat. The battle, fought from July 1-3, was the largest and deadliest of the American Civil War, with over 51,000 casualties.

2. Pennsylvania Turnpike opened: On July 26, 1940, the Pennsylvania Turnpike opened to the public. Stretching 160 miles across the state, it was the first long-distance, limited-access highway in the United States.

3. John Wilkes Booth's body returned to Pennsylvania: On July 26, 1865, the body of John Wilkes Booth, the assassin of President Abraham Lincoln, was returned to his family in Bel Air, Maryland, after being buried in a secret location in Washington, D.C. Booth was born in Harford County, Maryland, which borders Pennsylvania.

4. The first major league baseball game was played in Pittsburgh: On July 26, 1877, the first game of the National League's first season was played in Pittsburgh's Recreation Park. The game featured the Pittsburgh Alleghenys (later the Pirates) and the Boston Red Caps (later the Braves).

5. Three Mile Island nuclear accident: On July 26, 1979, a nuclear accident occurred at Three Mile Island, a nuclear power plant near Harrisburg. The accident, which was caused by a combination of mechanical and human errors, resulted in the release of radioactive gases into the atmosphere. While no deaths or injuries were reported, the incident had a significant impact on the public's perception of nuclear power.