The medina in Fes is unparalleled - it will surprise, delight, and offend you as you wind through it's maze of shops.
One of the highlights for those interested in seeing unusual professions is the leather dye vats. You don't need a map to find them, just follow your nose.
You can view the vats from above from the various leather shops that have 'viewing areas'. You will be astonished at the work going on below you. Cow and goat hides are soaked in large vats to clean and then to dye them. The dye colors are natural and come from plants and flowers such as poppy (red), saffron (yellow), and mint (green).
Men only work literally inside the vats stomping the hides down into the dyes - like grapes at a winery. They slather their legs in vaseline to ensure their skin doesn't get dyed in the process - a hazard of the workplace.
This is a site to see so don't forget your camera. And don't worry - if you are worried about the smell, the shop will provide fresh mint for you to inhale while peering over the edge to see this ancient profession in action.
How to find the vats? Most people hire guides to navigate them through the medina, so simply ask your guide - or just point your nose to the sky and inhale!