Netherlands, Belgium and France - Lots of languages and cultures, but they are all Western and pretty safe.
London, Scotland, and Ireland - No language barrier so it would be more comfortable. If this is your first big solo trip, this could be a great choice.
Egypt and Jordan - Personally, I wouldn’t go to Egypt as a solo woman. You might be fine, but there could be harassment, and you might face a tough situation if things went wrong. I found Jordan to have a very welcoming culture, but that was before the recent conflicts involving Israel and the US President, which could have changed how Americans are perceived.
Crosby said: @Rio
This should be a warning for many destinations. Most places are fine for solo travelers (even women), but maybe not for the first time.
I’ve acted as a ‘body guard’ for solo male travelers who couldn’t handle the attention in some areas. I actually felt safer as a solo female in Peru back in the 90s due to the attention men drew from the police.
For your first solo trip, I suggest Greece. Spend two weeks starting in Athens and then fly to islands like Crete and Rhodes. You’ll thank me later! It’s great that you’re going and not letting someone hold you back from your dreams! May to June is better in Greece.
Vance said: @Finley
Just a heads up, there have been earthquakes around Santorini.
That’s why I didn’t mention Santorini, coming from a real Greek! It will be the trip of a lifetime, and I’ll keep going back! Great food, beaches, and very safe for solo women.