trip to lviv ukraine as a us citizen?

Go to Lviv because it's a beautiful city with great architecture, bars, restaurants and cafes. It's a great city to visit whether you are on your own or not

As for meeting girls, that all depends how successful you are at meeting girls in the US. If you are the type of nice, respectful good looking guy who has no problem meeting girls in the US then you won't have a problem in any country

If you are going because you have fallen into the Internet myth that all Ukrainian women are gorgeous, desperate and just looking to have sex with any foreigner, the only girls you will meet are prostitutes. Ukraine is still a traditional conservative country and any decent girl does not sleep with men she just meets. Those are hookers whether they admit it or not. If your friend slept with her right away, bought her expensive gifts, gave her money, sends her money then the girl he hooked up with is a sex worker. She just hasn't been honest with him about it

A Ukrainian male friend of mine who got his Masters in the USA said American women are the easiest women to sleep with and they'll jump into bed with anyone if they are drunk while most Ukrainian women won't sleep with a man until they are in a committed relationship