Two regions on the same Cretaceous chalk, three hundred years apart. Traditional-method sparkling is the most cellar-driven wine tourism there is — most of what matters happens underground.
How a region qualifies
The region's principal output is traditional-method sparkling wine.
What it changes
Cellar tours run to fixed times and are genuinely cold. Book the grower visits ahead; the large houses can usually be walked into, the small ones cannot.