first timers to board

There is crime everywhere, including Zihua. That being said, a few basic rules will tend to keep you out of trouble just about anywhere you go:
Don't stumble around drunk at night, don't wear flashy jewelry, stay in the touristy parts of town after dark, get your cash at ATMs during daylight hours and be friendly and courteous to the locals. No guarantees, of course, but this has worked well for me over many years of travel.
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