When traveling to another country, which countries (as American) should I really not travel to alone as a woman?

I like to travel. I am an American. I have been to Mexico, Canada, England, Ireland, Germany, and France. I usually travel with a group of friends. I know the countries of the world have a full range of of opinions of women. When planning a trip for next summer, which which countries should I probably not tour without a male traveling with me? I can read, but I wanted to get some feedback from some people who may have experienced something that I didn't read about. Thanks.

When traveling to another country, which countries (as American) should I really not travel to alone as a woman?
Post Opinion