St. Charles County, MO
As of the 2010 census, the population of St. Charles County was 360,485, making it the third most populated county in Missouri. St. Charles County is part of the St. Louis Metro Area. Its county seat is St. Charles, which is the county’s second largest city. The largest city in St. Charles County is O’Fallon, with St. Peters and Wentzville the county’s third and fourth largest cities. It contains many of the northern suburbs of St. Louis as well as more urban areas. The county was organized in 1812 and named for the Italian cardinal Saint Charles Borromeo.
The wealthiest county in Missouri, St. Charles County is one of the fastest growing counties in the nation. It also includes an important area of vineyards and wineries whose distinction has been recognized. On its rural outer edge along the south-facing bluffs above the Missouri River is an area of numerous wineries, so that SH 94 is sometimes called the Missouri Weinstrasse. The area includes the Augusta AVA, designated in 1980 as the first American Viticultural Area by the federal government.
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