Girona

Girona is a city in Catalonia, Spain.

Heading north to France

From Girona Airport, walk east from the airport, under the AP-7 road and on a bit more until you get to the A-2 motorway. This is a toll road so you will have to sneak passed the toll operators (which is easily done with a little strategy). When you actually get onto the motorway, you will only need to walk about 1km north before you get to a gas station. From here you should easily be able to find people driving to France or beyond.

Heading south to Barcelona

Just walk to the Girona south/sud entrance to the highway AP-7 (it's easy to manage the way to there with simple map which you can get in the tourist office in the city). I would recommend using a sign.