Rosenblum Cellars was founded in 1978 in Alameda County. The winery is unusual in that it is located in the East Bay just across from San Francisco. It was founded by Kent Rosenblum, a veterinarian with an interest in wine, and today the business is still run by the Rosenblum family. The winery makes a large selection of wines sourced from grapes grown in virtually every region of California, from Sonoma and Paso Robles, to Contra Costa, Santa Barbara and Mendocino. Rosenblum makes about 50 wines a year. They are known for Zinfandels, Rhone-style reds and whites, and dessert wines. Many of the wines are vineyard-designated.