This denomination was carved out of the larger Chianti area in 1984 and was intended to encapsulate the best that Tuscany's flagship wine has to offer. It has been largely successful, though traditionalists grumble that revisions made in the 1990s have undermined the sanctity of the blend by allowing in such interlopers as Cabernet Sauvignon.
The wines of this region are mostly true to the spirit, if not the exact formula, of the revered blend created in the mid-19th century by Baron Bettino Ricasoli (whose descendants still make superb wine in the area).
Sangiovese is making up a minimum 75% and a maximum 100% of Chianti Classico. Canaiolo, Colorino and Mammolo are other traditional red vines and Baron Ricasoli recommended white Malvasia and Trebbiano to soften the tannins. This function is now more usually fufilled by ageing the wine, and Chianti Classico can be very austere and unapproachable when young. Cabernet Sauvignon and Merlot are occasionally added.
The area averages about 500m above sea level and is one of the coolest in Tuscany. Wet weather in summer can damage a vintage, but if this does not materialise then the longer ripening of the grapes brings about a more elegant and flavoursome fruit. This is the key to the pre-eminence of Chianti Classico in the district.