At the end of the Tertiary and the beginning of the Quaternary period, two plates collided under the Pyrenees: the northern plate slid under the southern plate. During the end of the ice age, the sea receded and began to draw the edge of Aquitaine.
The beginning of the Garonne spits rolled pebbles, various gravel mixed with clay, sand, hardpan, limestone and other shelly sands. The Garonne estuary is then diverted from the Arcachon basin to the north of the Gironde.
The numerous tributaries of the Garonne shape in the south of Bordeaux by going through the cradle of Girondine wine-growing: the gravelly ridges. That’s how the vineyard saw the light of day. The liana Vitis Vinifera was already there? Or did the Romans bring it with them; no one knows: but this frugal vine shoot shrub grows very easily on these poor soils of rolled pebbles and sand. Drainage is very important as the shrub needs to plunge its roots deep to survive, it sulphurs and then gives the best quality grapes. Warmed by the beautiful and warm sunny days, the white pebbles accumulate the heat and restore it during the night by offering through this process, optimal maturities.
The city has since invaded this area, but a handful of committed winemakers have allowed the wine-growing area to maintain itself. For some Grands Crus, it is an “in town” vineyard. Some are sometimes located on three towns of the Bordeaux conurbation. The fortification of the city protects them in part from possible frozen during winter.
