It turns out Sudbury is the most dangerous city in Ontario, if a new survey is to be believed. Advertisement 2 Story continues below This advertisement has not loaded yet, but your article continues below. Try refreshing your browser, or Sudbury ranked most dangerous city in Ontario, survey claims - Take our poll Back to video We apologize, but this video has failed to load. According to the survey, five of the 10 most dangerous cities in the world are located in South Africa. Article content Sudbury is ranked as the most dangerous city in the province with a score of 62.5.