Rockcastle County Assessor's Office
Rockcastle County KY PVA:
P.O. Box 977 205 E. Main Street
Vernon, Kentucky 40456
Phone: (606) 256-4194
Fax: (606) 256-8624
- Rockcastle County is a county located in the U.S. state of Kentucky. As of the 2010 census, the population was 17,056. Its county seat is Mt. Vernon. The county founded in 1810 and named for the Rockcastle River which runs through it. The river, in turn, is named for its majestic rock cliffs.