Sonoma, Lake, Yolo and Solano Counties.
From west to east, those would be: San Diego (San Ysidro) Otay Mesa Tecate Calexico Andrade
Owen, Scott. Woodford, Andersom. Shelby and Henry counties.
Starting directly south of Sacramento County is San Joaquin, then going counterclockwise the other seven counties are: Amador, El Dorado, Placer, Sutter, Yolo, Solano, and then Contra Costa.
5 counties border the county of Kilkenny. They are Laois, Wexford, Carlow, Tipperary and Waterford.