For me, only the Capital. We went to DC and went on the Captial tour. Though the best part of the DC trip was a bike tour of the monuments/memorials at night. Even though it was raining and freezing, it was so much fun. Hands were numb at the end lol.
A while back, we were on vacation in Florida and were going to go to Cape Canaveral to watch a Space Shuttle flight on our last day (I think the last launch, but I'm not sure) and it got delayed so we never actually made it, unfortunately.
We were also going to go to California and see stuff like Alcatraz, but that whole trip got cancelled due to COVID. Don't know if we will replan that trip yet or go elsewhere. Have a couple of options we are looking at for next summer.