She started with "The Grand Ole Opry" in 1962 -- "Grand Ole Opry" is the longest continuously playing radio program in the US, and can be heard on ne of Sirius-XM Radio.
Speaking of "The Grand Ole Opry" -- there are some AM radio enthusiasts in the UK who have fashioned quite directional "loop" antennae to pick up the signal from WSM, 650 kHz!