I was aware of Unicum long before I went to Hungary. One of my best friends from college spent a semester studying abroad in Budapest and brought me and my roommates back a bottle of it when she made her triumphant return to Baltimore. I remember it being awful. I did one shot and let the rest of our friends polish off the bottle.
Unicum is like Becherovka (the Czech herbal liqueur) or Jagermeister in that it is made from a combination of herbs. It doesn’t taste anything like either. According to the guidebook I borrowed from my parents when I was home at Christmas, it is a bitters made from over 40 herbs. As the recipe is a secret, that’s the closest I can get you to an actual number. Created by the Zwack family, Unicum was prescribed to the Austro-Hungarian Emperor Franz I in the late 1700s by the royal physician. I suppose it should be noted that the royal physician was a member of the Zwack family. Nothing like making use of the post to advance the family business!*
Having just spent a week in Budapest, my opinion of it has not changed; it’s still awful. But, when in Hungary…
*This information comes from the Eyewitness Travel, Budapest book, published by DK. In my edition (the 2007 version, which is when my folks were in Budapest), it can be found on page 195.