Ryanair fly to Carcassonne (about a 45 minute drive) from London Stansted, East Midlands, Liverpool, Dublin & Shannon.
Ryanair also fly into Perpignan (50 minute drive), Montpellier (1 ½ hr drive), Girona ( 2 hour drive), Nimes (1 ½ hour drive), and from Bristol into Beziers (35 minute drive).
It is advisable to check the websites of the airline, as new routes are regularly being added, and some routes fly only in the summer months.
By rail, the TGV routes stop in Narbonne, Beziers, Carcassonne & Toulouse.
Detailed instructions for getting to the house can be found here.