We are two U.S. citizens who will be staying in Hong Kong and would like to visit Shenzen

You can do that by applying for a 5 days visa on arrival at one of three designated border crossings between Hong Kong and mainland China. The most practical is Lo Wu (Luohu) that you can easily reach by Hong Kong suburban railways. You will cross the border on foot and on the mainland Chinese side you will apply for this visa on arrival. It will be granted to you, but the only drawback is the fact that the price of the visa is relatively steep 1,295 CNY for US citizens based on the reciprocity. Please, have in mind that the border crossing visa offices are open only from 09:00 until 16:30. To avoid crowds, you are advised to be at the border crossing even before the opening hours.

After your stay in Shenzhen, you can return back to Hong Kong by taking any border crossing and any mean of transport, high speed train included.

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