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As with any overseas travel, you are encouraged to leave a certified set of your travelling documents with someone in your home country and then to carry a set of certified documents with you (separate from your original documents). This is in the event of you losing your passport. Once at the project, you will be able to store your passport and valuables in a safe on site.
You will need to check online or with your local South African consulate to determine your Visa requirements. Tourists from many countries can stay up to 90 days on a visitor Visa, which is arranged upon arrival. This is not for all countries. Ensure you check well in advance to allow time to arrange a Visa in your home country, should it be required. Anyone planning to stay longer than 90 days will need to arrange a Visa prior to leaving their home country.
It is not possible to extend a visitor Visa once you arrive in South Africa.