I'll be staying one night in Barcelona in a couple of weeks' time, arriving late at night at BCN (23:30), onward flight the following day doesn't leave until 16:00

It will be my first visit to Barcelona so I intend to use the time to see as much as I can...! Guess I need to be back at the airport around 14.00 give or take.

Is it best to stay at/near the airport and head in to the city in the morning, or head into the city as soon as I arrive and stay at a central location?