The grapes for Les Cassagnes de La Nerthe are grown on the highest terraces of the Domaine de la Ranjarde vineyard in the Côtes du Rhône appellation, surrounded by green oak forest. Viognier is planted here, a variety that is not allowed in Châteauneuf-du-Pape. The vineyards are located at altitudes up to 600 feet above sea level and feature multiple microclimates with different soils of sand, clay, and shards of calcareous rocks that provide natural filtration. The grapes are harvested by hand at night or very early in the morning and carefully sorted after arriving at the winery. They undergo direct pressing early in the morning to benefit from the cool temperatures, preserving the aromas. The must ferments in stainless steel vats at low temperatures (59-65°F) to protect the flavors. The wine is aged for about 6 months in stainless steel vats on fine lees with regular stirring before bottling.