This tea, grown on Dongding (凍頂) mountain in Nantou County, was brought to Taiwan during the 19th century from the mainland's Wuyi Mountains. Its special qualities have been attributed to an almost continuous fog. Teas harvested in the spring are entered in a competition and the winners go for premium prices, fetching US$2,000 for a 600-gram package during the 1990s. Dongding oolong undergoes less fermentation than most oolongs. A 40-minute roasting over charcoal contributes to its flavor, which also has nutty, caramel, and chestnut elements.