Frederick County is a county located in Maryland, United States. As of the 2020 U.S. census, the population was 271,717. The county seat is Frederick. The county is part of the Capital region of the state.
Country: United States
State: Maryland
Founded: June 10, 1748
County seat: Frederick
ZIP Codes: 21701, 21702, 21703, 21704, 21705, 21709
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