1. In 1864, the Battle of Monocacy took place near Frederick, Maryland. Confederate forces under General Jubal Early attempted to invade the North but were repulsed by Union troops led by General Lew Wallace. The battle is known as the "Battle that saved Washington" because it delayed Early's advance and allowed Union forces to prepare for a counter-attack.

2. In 1904, the first successful flight of a manned, powered aircraft in Maryland took place at the old Belair Race Track in Baltimore. Inventor and balloonist Dr. Albert F. Zahm piloted his aircraft, which he called a "flying machine," for a distance of 1,300 feet.

3. In 1925, the Chesapeake Bay Bridge Commission was created to study the feasibility of building a bridge across the Chesapeake Bay. The commission's work eventually led to the construction of the Chesapeake Bay Bridge in 1952, which spans 4.3 miles and connects Maryland's Eastern and Western Shores.

4. In 1967, rioting broke out in Cambridge, Maryland, following the arrest of two African American men. The unrest lasted for several days and resulted in hundreds of arrests and millions of dollars in property damage. The Cambridge Riot was one of several outbreaks of civil unrest that occurred in cities across the United States during the summer of 1967, commonly referred to as the "Long Hot Summer."

5. In 2012, the Space Shuttle Discovery flew over Maryland on its final flight before being retired. The shuttle was mounted on a modified Boeing 747 and flew over several landmarks in Maryland, including the U.S. Capitol Building and the National Mall in Washington, D.C. Thousands of people turned out to watch the historic flyover.