While there are both red and white Bordeauxs, the name Bordeaux is primarily associated with the red wine blend. Red Bordeaux is a red wine that is always made from blending Cabernet Sauvignon wine and Merlot wine together, though the proportion of each depends on the location of the winery that made the wine.
In the Bordeaux region of France, where the wine is made, the Gironde estuary cuts through the center of the region creating two banks: a left bank and a right bank. It is a winery’s location on either bank that determines the proportion of Merlot to Cabernet inside each wine. If the winery is located on the Left Bank, the blend created will have more Cabernet Sauvignon than Merlot. If the winery is instead located on the Right Bank of the river, the wine will have more Merlot in the blend than Cabernet Sauvignon. This determination also allows us to make a few generalizations about the wine depending on the bank on which it was created. Here are the general rules: