I also visited the Natural History Smithsonian in Washington D.C. But, I am very sad to say it was partly disappointing. They did have some awesome exhibits, like the Dinosaur and Gems & Minerals displays, but those were the best things. There was no Blue Whale or even a good display of the Hope Diamond.
I loved the Dinosaur exhibit. It was very cool, and the complete sets of fossils they had were amazing! They did have a pretty cool copy of Sue, the Tyrannosaurus Rex, but I've seen the real one in Chicago. The mineral exhibit was the best though. The gems and rocks they had were great! I had lots of fun with my Dad trying to decipher what elements were in those marvelous minerals. But the best thing I saw in the Gems & Minerals exhibit was the fuzzy diamond! I also saw the sharpest mineral in the world.
I also went to the Library of congress that day. And I must say, the architecture of that building was utterly splendorous! The little names, designs, and details of that building was amazing! It makes sense that they have very high security in that place. They also had two of the most oldest and historic Bibles in the world! That building also had a tunnel to the Capitol, but for my nations most important building, it was hardly cool.