1. In 1817, the first Kentucky riverboat made its maiden voyage. The boat, named "The Orleans," was built in Louisville and carried passengers and cargo up and down the Ohio and Mississippi rivers.

2. On June 7, 1880, the first African American cadet graduated from the United States Military Academy at West Point. His name was Henry Ossian Flipper, and he was born into slavery in Thomasville, Georgia. Flipper went on to serve as a lieutenant in the U.S. Army.

3. In 1921, the infamous racehorse Man o' War won his very first race at Belmont Park in New York. Man o' War was bred and raised at the Nursery Stud farm in Lexington, Kentucky, and became one of the most successful racehorses of all time.

4. On June 7, 1936, the Ohio River flooded, causing widespread damage and loss of life in several states, including Kentucky. The flood was caused by heavy rainfall in the region, and more than 80 people were killed in Louisville alone.

5. In 1971, Muhammad Ali returned to the boxing ring after a three-year hiatus due to his refusal to be drafted into the Vietnam War. Ali's return fight was against Jerry Quarry in Atlanta, Georgia, but he would later fight several times in Kentucky, including a famous bout against Joe Frazier in 1975 dubbed the "Thrilla in Manila."