I spent a long weekend visiting V1 and V2 sites in France last Autumn. La Coupole and the V2 launch facility at Watten nearby are both well worth a visit. Although Coupole was never used in anger it has a history and the museum there is very good even when looking at it from a fairly informed and Nerdy viewpoint. Watten is the same. Well presented and a fascinating history. I combined these mainstream sites with a bit of foraging for the off the beaten track V1 launch sites like Carre Bois - basicall untouched since it was bombed in 1944 and the "original" V1 "Ski" site.