If you plan to arrive by train, it is the best that you take a taxi from the Carcassonne train station.
Train to Paris: Only 4 hours!
Train to Cote d'Azur: Only 4 hours!
If you plan to arrive by plain, the largest airport in the region is Toulouse.
Air from Toulouse: To many destinations inside EU!
Air from Toulouse: To some destinations outside EU!