Keukenhof GardensKeukenhof Gardens, which is the largest flower garden in the world. It's only open for a couple of months each year. Apparently some 7 million bulbs are planted each year.
At one point I decided to try to get a picture of one flower from every colour of the rainbow. It was hard to keep track of which colours I had gotten and which I had missed, but I seemed to have got most of them, and either way my camera's battery ran out of juice, so it decided I had gotten enough. My rainbow series is below, and check out the full gallery.