If you enter the souks from the north end (just past Rue de Mouassine) and follow round to the right you will find the dyers souks. Lots of brightly coloured scarves and wool suspended over the lanes on ropes to dry. Shopkeepers will want to arrange a headscarf desert style in the hope you will buy. Like in the rest of the souk if you are not interested don't let them wrap the scarf round you. A firm but polite "la shukran" (no thankyou) will do the trick.
If you are prepared to pay a small sum (5-10Dhs) you can go through behind the shops to see where stuff is dyed and have the natural pigments explained. This is actually very interesting and you can have a friendly chat with the guys there.
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