Garnett is a city in and the county seat of Anderson County, Kansas, United States. As of the 2010 census, the city population was 3,415.
Garnett was platted in 1857. Garnett is named for W. A. Garnett, a native of Louisville, Kentucky, and early promoter of the town of Garnett.
The city includes three places listed on the National Register of Historic Places: Anderson County Courthouse, Sennett and Bertha Kirk House, and Shelley-Tipton House.
The city is also home to the 1858 Garnett House Hotel.
According to the United States Census Bureau, the city has a total area of 3.20 square miles (8.29 km2), of which 3.10 square miles (8.03 km2) is land and 0.10 square miles (0.26 km2) is water.
Garnett is famous for its fossil finds from the late Carboniferous period. The lagerstätte is about 300 million years old and contains some of the earliest reptiles on earth.
The climate in this area is characterized by hot, humid summers and generally mild to cool winters. According to the Köppen Climate Classification system, Garnett has a humid subtropical climate, abbreviated "Cfa" on climate maps.
As of the census of 2010, there were 3,415 people, 1,419 households, and 862 families living in the city. The population density was 1,101.6 inhabitants per square mile (425.3/km2). There were 1,591 housing units at an average density of 513.2 per square mile (198.1/km2).