In the early 1990s, Baron Philippe de Rothschild, owner of Château Mouton Rothschild, was on vacation in the California Napa Valley. He was impressed by the opportunities for viticulture and asked winemakers who he could best meet. The name of Robert Mondavi was unanimously mentioned. Robert Mondavi had to leave his Italian family after an argument with his brother. He left for California in 1966, borrowed $ 100,000 and started his wine business. 7 years later he met Baron Philippe de Rothschild. The baron was impressed by Mondavi's passion and wanted to start a unique wine project in Napa Valley. Mondavi saw in this project a great opportunity to put Napa Valley on the map. In 1976, Robert Mondavi visited Château Mouton Rothschild to discuss the business aspects of the new project. They dined extensively and the wine flowed freely. To Mondavi's surprise, no business was discussed. At eight o'clock the next morning, he was invited to the baron's bedroom. The 66-year-old Grand Cru owner had a habit of doing business in his bedroom. His desk was also there. Both men discussed the new project that would unite the good of Bordeaux and Napa Valley. Mouton winemaker, Lucien Sionneau and Robert Mondavi Tim's son entered Mondavi's winery to determine the style of the new wine. It took three days for both winemakers to agree. Bordeaux and Napa had found each other. The first wine was named Opus and was made in 1979. It was an assembly of Mondavi's best wines. At that time there was no own vineyard or own wine company for Opus. A year later, the joint venture was made public and the name Opus One was born. During an auction in Napa Valley, a chest of Opus One raised $ 24,000. At that time the highest price for a California wine. Opus One became the first American ultra-premium wine. In 1991 the new winery for Opus One was built and the vineyard was built around the winery. Cabernet sauvignon, petit verdot, merlot, cabernet franc and malbec are cultivated in the 69 ha vineyard. Opus One is visited annually by 60,000 people who gain access only by appointment and for a fee.