Things we learned and some suggestions about the US national capital:
1. A bus tour helps to get orientated: the red bus tour was our choice because we liked the open top - it was very good, if a little grid-locked on Friday. Monday was better. There are two other touring companies; they all seem to overlap - be ready for glorification of wars and lots of statues of dead white men. Martin Luther King is given a token location - his feet are still encased in stone, unsculpted, because "his work was unfinished". (Alert: segregation in tourism can be seen here as the whites went to Roosevelt and Moslem/black tourists could be found at MLK.)
2. The city is clean - perhaps the cleanest city that I've ever visited. There are re-cycling bins everywhere but it is not clear whether people understand the purpose of separating garbage.
3. Food is expensive. We bought groceries for our breakfasts and snacks - cheese, crackers, fruit, cereal, milk, tea and coffee. $2.90 for two quarts of milk, $1.20 for a banana - US funds.
4. Public bus and metro service is excellent! The drivers and metro service managers were very pleasant and helpful. For seniors, $1 a ride practically anywhere; everyone else $2. If we went back, we would purchase a "smartride" card which is needed for transfers - over two hours. Eating out? Expect a minimum of $15 for a salad or a sandwich. Our best deal was the American University cafeteria where that same $15 got an all-you-can-eat buffet. The menu at the German restaurant around the corner from our Airbnb listed meals at $48.
5. Smithsonian museums and galleries are free - we went to the National Arboretum (and rose garden), the National Museum of the American Indian, the National Cathedral (not free), the National Art Gallery and especially the National Museum of African American History. (Tickets for the last one are on line about four months in advance of the visit, daily tickets go up at 6:30 am - our choice - or you can stand in line at 1:00 pm.) (It was warm outside and the air conditioning was fierce - we carried extra clothes.)
6. There are lots of demonstrations and a few vigils. We went to the demonstration for health care; an experience in sharing just a little in the US underbelly with lots and lots of police presence. We saw the vigil against torture (and Guantanamo) from the bus. Probably best to leave before arrests start unless you are rich or famous enough to get media attention.
We were blessed with fantastic weather and would easily go again!