Byrnes Mill Map
Byrnes Mill is a city in Jefferson County, Missouri, United States. The population was 2,910 at the 2008 estimated census. It was 2,376 at the 2000 census.
Byrnes Mill is located at 38°26?7?N 90°34?26?W / 38.43528°N 90.57389°W / 38.43528; -90.57389 (38.435197, -90.573838).
According to the United States Census Bureau, the city has a total area of 5.1 square miles (13.2 km²), of which, 5.0 square miles (12.8 km²) of it is land and 0.1 square miles (0.4 km²) of it (2.75%) is water.
Nearby cities include Arnold, Ellisville, Ballwin, Manchester, Barnhart.