Oldham County is a county located in the north central part of the U.S. state and commonwealth of Kentucky. As of the 2020 census, the population was 67,607. Its county seat is La Grange. The county is named for Colonel William Oldham.

La Grange is a home rule-class city in Oldham County, Kentucky, in the United States. The population was 10,067 at the time of the 2020 U.S. census. It is the seat of its county. A unique feature of the city is the CSX Transportation street-running mainline track on Main Street that sees multiple trains in both directions.