Czech wine of these festivals in Znojmo, Mikulov, Brno and Mělník will feature samples of hundreds of local wines as well as local music, dancing and cuisine. These wine-festivals take place in big towns apart from the wine-producing areas as well (such as Prague). Czech wine law classifies wine according to the origin of the grapes and the ripeness of the grapes determined by measuring the must weight in the grape juice at the time of harvest. Sugar content is expressed in units of °NM on the Czecho-Slovak Normalised Must-Weight Scale (Czech: "Normalizovaný moštoměr"), which indicates how many kilograms of sugar are
Wine in China "materia medica" compiled in the late Han, states that grapes could be used to produce wine. In the Three Kingdoms era (220–280 AD), Wei emperor Cao Pi noted that grape wine "is sweeter than the wine made [from cereals] using ferments and sprouted grain. One recovers from it more easily when one has taken too much." Grapes continued to be grown in the following centuries, notably in the northwestern region of Gansu, but were not used to produce wine on a large scale. Wine thus remained an exotic product known by few people. Not until the Tang dynasty (618–907) did