Hello! This is a pretty common phrase in English.
“Up in [location]” or “Down in [location]” is a colloquial way of saying “at [that location]”. Often we say “up in [location]” if the location is North of the speaker, or “down in [location]” if the location is South of the speaker, but people use this very loosely.
For example, I live in San Francisco, so I might say:
“I’m spending the weekend up in Portland with my good friends”
Or
“My aunt lives down in Los Angeles”.
If the location is close, we will often say “over to [location]”, as in:
“My sister had a party so I went over to her house on Friday night”
I hope that helps!