Explore the Spanish colonial revival architecture of Balboa park. You can visit the many museums they have available. Grab a drink at Panama 66 then head to the Prado for lunch!
In the historic district of Old Town San Diego you can experience Mexican heritage by watching live mariachi bands and folklorico dance. You can explore the many shops and visit the Whaley house if you want a supernatural experience.
You can find many places to grab a bite to eat, or pick up a coffee while you walk around and visit the shops at liberty station.