What is the best way to get to Granada from Barcelona - rental car, train or air?
Vuele con Vueling (= Fly with Vueling).
What is this 'best'? Something to do with comfort, journey time, money, what? Flights as above. Train - www.renfe.com
Bus - www.alsa.es
i have taken the night train, "the hotel train" and it was excellent. leaves barcelona around 9 pm and arrives around 9 am. great dinner and reasonable breakfast. had first class car and private cabin with shower and toilet. cost maybe $200. check it out fun time. have fun, be safe.
For that leg, I'd go with Roberto's recommendation (I never got the connection with the name before).