| Jefferson County Washington Cities/Towns - Brinnon, Discovery Bay, Marrowstone, Port Hadlock, Port Ludlow, Port Townsend (County Seat), Quilcene |
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Your Ad Here Jefferson County is a county located in the U.S. state of Washington. As of 2000, the population was 25,953. The county seat is at Port Townsend. History The county was formed out of Thurston County on December 22, 1852, by the legislature of Oregon Territory. It is named after Thomas Jefferson. |