Munster and Leinster could both play Champions Cup semi-finals in Bordeaux if they get through their quarter-finals this weekend.
The venues for the last four games were announced on Thursday and, if Leinster meet La Rochelle and Munster take on Racing 92, there will be an exodus from the two provinces to the south of France.
If Scarlets overcome La Rochelle then Leinster will be rewarded with a home tie at the Aviva Stadium against the Welsh side.
Munster, meanwhile are guaranteed a trip to France if they beat Toulon with Bordeaux (if they play Racing 92) or Saint-Etienne (if they play Clermont Auvergne) the possible venues.
The matches will be played on the weekend of April 21st and 22nd.
Champions Cup semi-finals - 21/22 April
SF 1: if Leinster Rugby v Scarlets - Aviva Stadium (Dublin)
SF 1: if Saracens v Scarlets - Ricoh Arena (Coventry)
SF 1: if La Rochelle v Leinster Rugby - Stade Chaban-Delmas (Bordeaux)
SF 1: if La Rochelle v Saracens - Stade Chaban-Delmas (Bordeaux)
SF 2: if ASM Clermont Auvergne v Munster Rugby - Stade Geoffroy Guichard (Saint-Etienne)
SF 2: if Racing 92 v Munster Rugby - Stade Chaban-Delmas (Bordeaux)
SF 2: if RC Toulon v ASM Clermont Auvergne - Alllianz Riviera Stadium (Nice)
SF 2: if RC Toulon v Racing 92 - Allianz Riviera Stadium (Nice)
Champions Cup final - Saturday, May 12th
TBC v TBC - San Mamés Stadium, Bilbao (17.45)