A huge array of beaches outside Barcelona are located up and down the coast. Getting there is easy by train. Catch RENFE trains from either Plaça Catalunya, Passeo de Gracia or Sants stations, and within 30 mins, you could be at a glorious beach of your choice.Going up the coast, the train runs next to the beach, so just jump off at one of the numerous stations and you'll practically be on the sand.
A host of charming and interesting towns and cities are very close to Barcelona, either by the beach or inland. A few examples: Sitges , Castelldefels , Figueres , Girona ..
Many visitors consider a trip to Montserrat to be a major highlight. It is a spectacularly beautiful Benedictine monk mountain retreat about one hour from Barcelona by train. Catch the FGC train from Plaça Espanya station, and go to either the cable car stop or the funicular stop.
Probably the best and easiest park to get to is Parc Collserola. It's only 20mins outside Barcelona centre, and is an area of unspoilt, beautiful nature.
Plenty of birds and animals to be spotted in the deltas, mountains and other remote areas around Barcelona.