Mount Vernon
Here’s a site that actually has no associations with the military! It’s one of only a few recreational spots that make the list (a distinction it shares with the Disney parks!). The home of George Washington, which is a National Historic Landmark, is known as “P-73.”
So even though it’s located in northern Virginia, it’s actually separate from the prohibited zone around Washington, D.C., which is P-56. Even would-be aerial photographers are not exempt from the no-fly restriction; their site says that aerial photography is “rarely permitted.”