The trip in September is just about planned.
Belfast to Cork. Cork to Roscoff ferry.
First day drive to just south of Nantes for a night, then to La Rochelle for a night.
Two nights booked at Sarlat at the place you recommended Don, then back across for a couple of posh nights Bordeaux.
A night near Bergerac to finish off seeing Dordogne before a drive south to Mont de Marsan.
After that, a night in Biarritz before Pamplona (via St Jean pied de port - thanks Graham).
last night in Getxo before the ferry from Santander back to Cork and the road north home.
two exciting weeks!
Ian