Duncan is located at the junction of Kentucky Route 501 and Kentucky Route 837 12 miles ( 19 km ) east - northeast of Liberty .
Duncan is an unincorporated community in Casey County , Kentucky , United States .
community is located at the junction of Kentucky Route 501 and Kentucky Route 837 12 miles ( 19 km ) east - northeast of Liberty .
Duncan is an unincorporated community in Casey County , Kentucky , United States .