Corton-Charlemagne is a Grand Cru appellation for white wines, predominantly Chardonnay, produced across much of the top portion of the oval-shaped Montagne de Corton hill, in the Côte de Beaune district of Burgundy. Location The appellation was introduced in 1937 and covers multiple individual vineyard climats across the almost circular hilltop. Broadly speaking, however, the overall site runs (if looking at the hill from above) from an 11 o'clock position (due west, in the Le Charlemagne portion of the hill which almost runs down to the hill's base) anticlockwise to a four o'clock position (roughly due east, in the higher, thinner Le Corton portion). The majority of the site falls within the Aloxe-Corton commune but the En Charlemagne section, which almost faces northwest, is in Pernand-Vergelesses while, on the opposite side of the hill, facing east and beyond Les Renardes, lie the Le Rognet et Corton, Hautes Mourottes and Basses Mourottes climats in Ladoix – all of which can, in certain sections, produce Corton-Charlemagne. In all, there are around 52 hectares (130 acres) of vineyard entitled to use the Corton-Charlemagne title. The Corton-Charlemagne title is also effectively identical to the less-used Charlemagne Grand Cru appellation whose production parameters are practically identical. The former is more often encountered, however, due to its fame. Geography The hill of Corton itself is a large outcrop of limestone, set slightly apart from the main Côte d'Or escarpment that runs broadly north to south from Gevrey-Chambertin and southern Dijon to Santenay and Maranges in the south. The Corton hill roughly marks the northern end of the Côte de Beaune subregion and abruptly halts the vineyard-strewn plain which flows north from Beaune. The top of the lozenge-shaped hill is covered in dense woodland, which is regarded as a crucial component in the mesoclimate. In 2017, rumors that this 66 hectare (163 acres) zone was to be sold and possibly developed with further vineyards led producers to band together to safeguard its survival. The trees are replaced by vineyards from about 345 meters (1130ft) downwards. Vines occupy the slopes of the hill for almost its entire circumference, although the Grand Cru rating covers only the southern portion of the hill, sweeping majestically around from due east to due west. The Le Charlemagne, Les Pougets and Les Languettes lieu-dits, facing southwest to southeast are responsible for most of the Corton-Charlemagne output. However, while the red wines of the Corton appellation are generally labeled with the name of a specific climat, this is not the case for Corton-Charlemagne – probably reflecting a greater degree of homogeneity between the three parcels. The clay topsoil has eroded away from the top of the slope nearest the trees, leaving a limestone-marl mix most suited to white grapes, which has historically been the source of Corton-Charlemagne. Further down the slope there is more clay, iron, scree and fossil-rich soil more suited to Pinot Noir. The eastern side is a touch warmer – being more exposed to the morning sunshine – and richer in the marlstone which is so well suited to Pinot Noir. Production While many Corton-Charlemagne wines will be predominantly (if not entirely) produced from Chardonnay, official regulations allow up to ten percent Pinot Blanc within the vineyards. Furthermore, the finished wines are legally allowed to contain up to 30 percent Pinot Blanc. This leeway (often found in the white appellations of Burgundy) is partly due to the genetic instability of Pinot Noir which often shares the vineyard area with Chardonnay on the Corton hill. Given that Pinot Noir vines have been known to mutate into Pinot Blanc, production from what was once a red vine can potentially be switched to white wine without losing grand cru status. Yields are fixed at a maximum of nine tons per hectare (3.6 tons per acre) with a juice yield of 4800 liters per hectare. For comparison, the whites of Aloxe-Corton have their yields set at 10.5 tons per hectare (4.2 tons per acre) with juice yields of 5500 liters per hectare for Aloxe-Corton Premier Cru and 5700 liters per hectare for "village" level Aloxe-Corton blanc.