Looking for a something a little bit different in Washington DC and without the overwhelming crowds? Try the US Botanic Garden, a gorgeous cacophony of green right by the Capitol Building. You can visit a tropical rainforest, a desert, and see carnivorous plants among lots of other things in the huge greenhouse, and kids will enjoy exploring all the nooks and crannies of the outdoor gardens. Our family always enjoys a stop here to escape the crowds of the other attractions on the National Mall.