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.
Area code 405 serves the U.S. state of Oklahoma. It covers the Oklahoma City Metropolitan Area including cities such as Oklahoma City, Edmond, El Reno, Norman, Stillwater, Shawnee, Chickasha, Tuttle, and Moore.he other three area codes serving Oklahoma are 539 and 918, which cover northeastern Oklahoma (including the city of Tulsa); and 580, which serves western and southern Oklahoma.