The Newseum was a museum in Washington D.C. all about the U.S. Constitution's First Amendment. Sadly, it has closed as of 31 Dec 2019 (but might relocate and reopen). For reference, United States Constitution Amendment I:

Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.

I visited in 2019 and thoroughly enjoyed it. The museum explored the press and free speech from many perspectives including historical, critical challenges over time, delivery media (print, photographs, broadcast audio or video) and cross country comparative. Outside the building there were many newspaper front pages from around the world displayed side-by-side—all updated early each morning.

The museum was sponsored by the Freedom Forum, which continues the mission of the museum.

Such an important topic and mission—helping Americans understand not only this right but how it has been implemented, challenged, and protected. We need this museum back!