Killeen , TX is located in Bell County . It has a population of 136,378. It’s known for the Fort Hood military base. The base includes the 1st Cavalry Museum, featuring an outdoor exhibition of historic military vehicles. On the Central Texas College campus, the Mayborn Science Theater hosts planetarium shows. Lions Club Park has a swimming pool and a playground. East of the city, Temple Lake Park has picnic areas, a beach and bass-filled waters.