From Barcelona, take the C33 road towards Girona and leave it at Exit 2 (Parets, Vic, Puigcerdà).
Take C17 (former N152) towards Vic. In Vic you need to change to C25 towards Girona. Take the exit 183 and follow the sign for Roda de Ter.
After approximately 1.4 km turn left and take the rural road next to the electrical tower for about 200 m. Turn left again and after 300 m you'll be in Carboneres.

Mas Carboneres GPS Coordinates 

Latitude: 41º 58' 06,41'' N            Longitude: 2º 17' 23,27'' E