1. In 1966, the Black Panther Party was founded in Oakland, California. The organization eventually expanded to other cities, including the District of Columbia. The Black Panther Party advocated for African American civil rights, including an end to police brutality and racial discrimination.

2. In 1979, the National Air and Space Museum opened its doors to the public. The museum, located on the National Mall in Washington, D.C., houses a vast collection of artifacts and exhibits related to aviation and space exploration, including the Wright Brothers' 1903 Flyer and the Apollo 11 command module.

3. In 2007, thousands gathered at the Lincoln Memorial in Washington, D.C., to participate in the National Equality March. The march was organized to advocate for LGBTQ+ rights, including marriage equality and an end to discrimination based on sexual orientation or gender identity.

4. In 1987, President Ronald Reagan signed the Intermediate-Range Nuclear Forces Treaty with Soviet leader Mikhail Gorbachev. The treaty was a significant step in reducing tensions between the United States and the Soviet Union during the Cold War.

5. In 1973, the Supreme Court issued its landmark decision in Roe v. Wade, which legalized abortion nationwide. The decision has been a subject of ongoing debate and controversy, and has had a significant impact on the political and cultural landscape of the District of Columbia and the United States as a whole.