There are certain areas in the world which is considered no go. This means that they are considered so dangerous that randomly stumbling into the neighborhood is likely to result in getting mugged, and that is the least that could happen. It becomes especially dangerous if your appearance is much different than the majority demographics of the area, though they still tend to kill each other regardless.
Unfortunately, these areas exist in the United States, which is surprising considering it is the #1 economy in the world. People coin these areas as “the hood”, or the “ghetto”. Some places are so bad that even the police avoid it. They instruct you not to stop at any red lights, and make sure your car windows are rolled up and doors locked.