According to the United States Census Bureau, the city has a total area of 1.9square miles (4.9Square kilometers), of which, 1.9square miles (4.9Square kilometers) of it is land and 0.04 square miles (0.10Square kilometer) of it (1.58%) is water. Kirby is a city in Bexar County, Texas, United States. It is an enclave of San Antonio and is part of the San Antonio Metropolitan Statistical Area. Founded as an agricultural settlement along the Southern Pacific railroad, the city was transformed into a suburban community upon its incorporation in 1955. The population of 8,673 (2000 census) is made up of diverse individuals with numerous backgrounds. German, Hispanic, and hobo elements have all affected the overall culture of the city.