For the wine region, see Napa Valley AVA. Napa County is a county located north of San Pablo Bay in the northern portion of the U.S. state of California. As of the 2010 census, the population was 136,484. The county seat is the City of Napa. Napa County was one of the original counties of California, created in 1850 at the time of statehood.
Area code 412 is a Pennsylvania area code that covers Pittsburgh and some of the surrounding areas. Area code 412 overlays the area code of 878. Pennsylvania has area codes of 215, 267, 272, 412, 484, 570, 610, 717, 724, 814, 878.
(April 2013). Area codes 630 and 331 are area codes, under the North American Numbering Plan in the United States, that cover portions of Chicago's near and far western suburbs, including the majority of DuPage County, Illinois.he main area code, 630 was split off from area code 708 on August 3, 1996. Within a decade, 630 was close to exhaustion due to the explosive growth of the Chicago suburbs and the proliferation of cell phones and pagers.