Hilliard is a city in Franklin County, Ohio, United States. The population was 28,435 at the 2010 census with a census estimate of 31,012 in 2013. It is a suburb of Columbus, Ohio and part of Norwich Township. Hilliard is home to the Early Television Museum, the second largest First Responders Park in the United States, Heritage Rail Trail and Bo Jackson Elite Sports Facility. Hilliard also has the only flag from the World Trade Center that is not in a museum. The flag is located in front of the fire department on Northwest Pkwy.