Tijuana, the city at the western end of the U.S.-Mexico Border. Many studies rate this town as the most violent place in the world. The city certainly has one of the world’s highest homicide rates. The city saw 138 murders per 100,000 residents last year. That’s compared to 3.6 per 100,000 in New York City. Tijuana has had one of the highest murder rates in Mexico, and also worldwide.