The Kentucky Science Center, previously known as the Louisville Museum of Natural History & Science and then Louisville Science Center, is Kentuckys largest hands-on science museum. Located in Louisville, Kentuckys "Museum Row" in the West Main District of downtown, the museum operates as a non-profit organization. It was founded in 1871 as a natural history collection, and now more than half a million people visit the museum annually. More students in Kentucky take field trips to the Kentucky Science Center than to any other destination. There are about 550,000 visitors annually. A special hands-on area for children younger than seven was renovated and renamed KidZone in 1998, featuring six educational activity areas. The building itself is located at 727 West Main Street, and takes up 150,000 sq ft (14,000 m2). This includes a four-story digital theater, built in 1988 with a renovation in early 2014, in which three million people have seen at least one of the 45 different films shown there. The distinctive cast-iron facade limestone building was originally built in 1878 as a dry goods warehouse. The city purchased the building in 1975 and the museum moved into the premises in 1977, subsequently winning several design awards for its preservation of an older building.