In the narrow streets of Old Hanoi there are several small pagodas that do deserve a visit. Most of the temples are open to the public, but you do have to be respectful. To visit a pagoda you have to dress properly. At the entry you have to take off your shoes. Photography inside the small pagodas should be avoided.
Hanoi is, as the rest of Vietnam, a safe place for tourists. But you do have to be careful, specially in overcrowded streets. My mobile phone was stolen in a street in the center of Hanoi. Some local pickpocket took advantage of the chaos to slip his hand in my pocket and take my cell phone.
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