1. In 1790, President George Washington signed into law the Residence Act, granting land for the creation of a new capital city along the Potomac River, which eventually became Washington D.C.

2. In 1863, Union troops crossed into Virginia from Maryland to begin the Gettysburg Campaign, a pivotal moment in the Civil War.

3. In 1915, the National Advisory Committee for Aeronautics (NACA), a forerunner to NASA, was established in Washington D.C. to develop and conduct research in aeronautics.

4. In 1964, the U.S. Senate passed the Civil Rights Act, which banned discrimination based on race, color, religion, sex or national origin in voting, employment, public accommodations, and education.

5. In 2018, Washington D.C. celebrated its first-ever LGBTQ Pride Month, with a month-long series of events and festivities held throughout the city.