Yes, Eid is right after the end of Ramadan. For us, not a lot happens, but for Moslems it is a bit like Christmas over here. All the children get presents and new clothes and there is a general air of festivity after the month of fasting. If you have Tunisian friends you may be invited to join them which is lovely. For Europeans it simply means that everything gets back to what is accepted as 'normality' in the country and we can, once again, sit outside in the sun having a meal or drink (at least you know the Golf Brau will be fully functional then

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One important point - make sure you don't run out of cash as it is a holiday season and the ATMs may run dry and not be topped up as frequently as usual.
If you put Eid into Google you will get a lot of information on the festival around the world.