Washington County    County Board    City of Hartford    Hartford Area Development Corp.    Village of Slinger    Village of Germantown    Germantown Chamber of Commerce WSOR runs across southwestern Washington County. Communities in Washington County include: Hartford, Slinger, and Germantown. WSOR serves Washington County from the east from its North Milwaukee yards. From the northwest, Washington County is served from the Horicon terminal. Washington County is located in southeastern Wisconsin, north of Waukesha County.