Sections of town one would consider dangerous?

Phoenix AZ

Description

I'm originally from near Baltimore, MD. There were sections of the city that were infested with drugs. Streets you walked up and literally 24/7/365 rain or shine, covid or no covid people would yell out to every passerby what they were selling "Hard, Soft, Dope, Ice" for example. Depending on one's preference I am wondering if there are any such sections/specific blocks around here that are the same way. Places that should be err, umm, "avoided" by someone new in the area like myself. Thanks in advance.