Henna is a dye that comes from the chopped dried leaves of lawsonia inermis, a bush commonly known as henna. This product enjoys different uses in the field of cosmetics, not only as hair dye, but also to create temporary tattoos. Anyone strolling along the Decumanus at the Great Universal Exposition, will certainly have come across girls of all ages with their hands decorated with these highly exotic tattoos. In fact, we could say that henna tattoos are one of the icons of Expo 2015. For anyone interested, the dedicated room inside the Qatar Pavilion, is certainly the best place. In fact the tattooing is free here but (for religious reasons), only women can be tattooed. But don't despair! In fact, there are other pavilions that offer these tattoos to all visitors, with a price ranging from 5 to 15 Euro according to the size of the tattoo itself, and where you can choose its design. This author tried those at Qatar and I have to say I was very satisfied. After a brief wait (around 20 minutes), I was welcomed by a young lady in traditional clothes who had me sit by her side on a little divan. I then asked for a tattoo on my hand and she gave free rein to her imagination, drawing a splendid rose. The consistency of henna is that of a cream. Initially, when it's still fresh, its color is a strong brown, but after letting it dry (for around an hour), this begins to peel away to reveal the color that remains on the skin: a very dark orange. The tattoo remains as it is for a few days, then it slowly begins to fade. You'd never have thought that Expo could be a temporary tattoo. But that's what happened, and it's one of the best memories that remain of the Great Exposition.