Tibetan is a special nationality, do respect the local customs there or you might have trouble with local people.
Tibetan people believe in Buddhism, they have a lot of customs related to their religious belief. Visitors should respect local customs and the traditions while travelling in Tibet. Besides, the political issues are sensitive as well, avoid talking about this with your tour guide, driver, monks and local people.
Here is something you must read before going to Tibet.
1. Do not talk about sensitive topics like politics, the Dalai Lama's issue when in Tibet.
2. Do not try to talk with some lamas about their religions and political position.
3. Walk clockwise around Barkhor Street, especially during the peak hours of pilgrimage from 9 am to 6 pm.
4. Walking wise around the Kora, the praying Pagoda, like Barkhor Street, the Monastery Kora.
5. Do not take photos inside the Chapel of Monastery unless you get the permission. 5. Also ask permission before taking pictures of Tibetan people, Sometimes you need pay them money or give them a gift like a piece of chocolate.
6. Monasteries are holy place in Tibet, Smoking is not allowed. And please dress properly. Not in shorts.
7. If you have a chance to visit a local family, let the oldest people go first when you walk together with them. Do not touch the heads of children with your hands. If the family invites you to have dinner with Tibetans, when the host hands you something, for example, a cup of wine hold it with both hands to show your respect. Do not drink wine fast, otherwise the host will give you more wine until you are drunk.
8. Do not buy anything made from wild animals' skin or bones, as it may cause problems when you try to leave the area.
9. Bring some small gifts like pens, pencils or candies, the Tibetan Children like them very much
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