In general I like art museums, especially old European landscape paintings; if time archaeology related museums, major monuments or historic structures, castles, remains from defunct civilizations; possibly parks except that I could see plenty of parks in the USA or even in Michigan.
I took solo trips to: Montreal and London, England, both when I wrongly believed I could only see one city per trip; Italy, Greece, the Netherlands, northern Belgium, Spain; Lithuania but I was there for a class and I didn't see much; parts of Southwest-Central Florida; When I was a kid my parents took me to New York, Chicago, and Washington D.C. [I have a woman cousin in a generation above me, who is at least 70; last time I saw her she said if I ever come back to New York she would be happy to meet me at almost any restaurant or museum]
I used to think I would go to France and Germany on my next trips. That was before the pandemic and my mom and an aunt being mortified at me for going to Spain because of the war in Ukraine. My mother will be horrified no matter where I go. I always feel like when planning a trip I am sneaking around behind my mom's back doing something terrible that I am not supposed to do. My mom thinks I am nuts or worse for traveling.
In my mother's mind: Germany is off limits because of World War II and the Holocaust/ nazi genocide; there were some mass shootings in Paris in my lifetime. I don't know why I have not worried about whether it is safe to go to Europe in 2022 or 2023 as somebody of Jewish heritage. I am not at all religious.
I have thought about laying off going to Europe and going to Mexico or Peru. I am aware that Mexico is supposed I be too dangerous. I would see museums in Mexico City, Mayan Ruins, and possibly something else I recommended in a guidebook that I could make time for. If I went to Peru, I suspect that I would want to include ancient Inca ruins and museums and travel to specific sights while avoiding spending a lot of time hiking on trails. I have no known major health problems.
Is there any way it could be safe to travel solo to Mexico?
Or I could just put off going to other countries and find a good city in the USA that has good museums or sites nearby. I understand that Los Angeles has the Getty museum. I haven't figured out whether Los Angeles is safe enough and I wonder whether the traffic is so terrible that I might get stuck in traffic for 2 hours or more each day. [Half my mother's relatives moved to California when she was a kid in the 1950's to 1960's. I have multiple second cousins and relatives who live in California, I don't even have all their names, and I doubt they know I exist and I have some doubt about whether it is worth my trying to contact them].
I understand that Nashville, Tennessee has a replica of the Parthenon. That is why I have vaguely thought of going to Tennessee.
Where do you suggest I go next?