Yet another case where knowing language phonology helps immensely. You might not know where Porto is, exactly, but tracing the language narrows it down a bit.
I don’t want to judge, but obscure geography? The second biggest portuguese city and one of the best/most influential football clubs in the world. Maybe obscure for the average guy, but for european geography this is a standard
I looked at the first question, assumed it was talking about state capitals without looking at other questions or instructions and quit when I got mad that I couldn't figure out what state I had left out from my attempts.
I definitely need some coffee. I couldn't figure out why Taiwan wasn't accepted instead of Taipei, why Freeport wasn't accepted instead of Nassau, and I was trying all the British Isle capitals for Perth. And, to start off wrong, I was trying all the state capitals near New York. Forget the coffee, I need a nap.
Except yes the Karachi one was a bit unexpected. But still not hard.