You won't look at your shoes or handbag the same way again after visiting this leather tannery in Fez, Morocco.

Leather is one of the products Morocco is most renowned for, and every tourist will have seen the leather shoes, bags, wallets and so on stocked in the street stalls that line the medinas (the maze-like districts found in most cities). But hidden amongst the jumble of shops and the tangle of streets, you’ll find a colorful, fascinating and smelly insight into how your bags and shoes were made – at one of Morocco’s leather tanneries.

Here, you can watch tanners stand knee-deep (or even waist-deep!) in giant concrete vats as they process and dye animal skins. This includes everything from scraping the hair or fur off the skin; removing any leftover bits of animal fat; softening the skin using all sorts of “natural” products such as pigeon dung, cow urine and even animal brains; washing the hide; coloring it in dye baths made of different types of bark; and finally, stretching the skins out to dry. It’s a truly captivating process that will leave you with a lot more respect for the leather goods you own, as well as empathy for the tanners and the gritty work they do.

This particular tannery found in the city of Fez is the oldest in the world and dates back to the 11th century. To see it, you’ll have to mount the stairs in one of the many leather shops in the leather souk (the section of the medina dedicated to leather goods). Many of the stores have “viewing galleries” built into their shops where you can watch the men at work.

Listing an address for the tannery is somewhat futile, given how confusing it is to navigate the streets of Fez, but don’t worry because there’s a surefire way to know when you’re getting close to it. Just follow your nose – the smell emanating from the tanneries is overwhelming to say the least (hardly surprising now that you know what’s in the vats right?)… you won’t miss it!