1. In 1777, the Continental Army, led by General George Washington, celebrated Christmas Eve by crossing the icy Delaware River from Pennsylvania into New Jersey to launch a surprise attack on Hessian troops at Trenton. This famous battle, known as the Battle of Trenton, was a major turning point in the American Revolution.

2. December 24, 1826, marked the death of John Adams, the second president of the United States. Born in Massachusetts, Adams played a key role in the Continental Congress that declared independence from Great Britain. After his presidency, Adams retired to his home in Quincy, Massachusetts, where he continued to promote American ideals until his death at the age of 90.

3. On December 24, 1868, the first national Christmas tree in the United States was lit by President Andrew Johnson. The tree was located on the White House lawn in Washington, D.C., and was decorated with strings of popcorn, nuts, and cooked cranberries.

4. In 1906, December 24 marked the arrival of the first long-distance telephone call in Pennsylvania. The call was made from the Bell Telephone Exchange in Pittsburgh to Philadelphia, a distance of over 300 miles. This historic moment was celebrated as a major milestone in the development of telecommunications technology.

5. December 24, 1969, saw the opening of the Pennsylvania Turnpike, a major highway connecting the east and west coasts of the United States. The turnpike, which stretches over 550 miles from Ohio to New Jersey, was a major engineering feat and has played a crucial role in the development of interstate commerce and transportation in the United States.