Which region of the northern Rhône can only produce wines made from 100% Syrah?

In the northern Rhône Valley, Cornas is the only appellation that exclusively permits the production of red wines made from 100% Syrah. This regulation is a key characteristic of the Cornas AOC, which emphasizes the strength and purity of the Syrah grape in the region. The focus on a single grape variety allows for a distinctive expression of the terroir, resulting in robust and intense wines that reflect the unique soil and climate of the area.

Other appellations in the northern Rhône, such as Côte Rôtie, Hermitage, and Condrieu, allow for different production regulations. For instance, Côte Rôtie can blend Syrah with up to 20% Viognier, creating a different style of wine with aromatic complexity. Hermitage also permits a blend of Syrah and small amounts of white grape varieties, which can add nuance and texture. Meanwhile, Condrieu is exclusively focused on the Viognier grape, producing white wines instead of red. Thus, Cornas stands out for its strict regulations regarding Syrah, setting it apart from the other mentioned regions.