United States Botanic Garden

Gardens in National Mall

Image by Barbara Noe Kennedy Lonely Planet

Built to resemble London’s Crystal Palace, this garden's iron-and-glass greenhouse provides a beautiful setting to view orchids, ferns and cacti. When you're done with those, seek out the so-called 'Corpse Flower,' Amorphophallus titanum, whose name translates to 'giant misshapen penis’ and whose erratic blooms smell like rotting flesh. Mmm! Alas, it only blooms every three to five years and it's not on show during its hibernation.