You don't give us much to go on. Yes, both are in cities, but beyond that, these are very different schools.
Click on "Why a woman's college" on Barnard's website and see how you feel about what is written. That should give you a good idea of whether Penn or Barnard is your more ideal destination.
My D attended Barnard and chose it over Brown to apply ED. She has graduated, but would still make the same choice.
Others would feel completely differently.