In the 1960s and 1970s, nearly 40 acres (16 ha) of the city's downtown were razed in an attempt at urban renewal, as population and businesses had moved to a suburban fringe along newly constructed highways. The Keystone Hotel and Worth Block (former home of the House of Lords) were notable historic structures that were demolished. Christman's Department Store stands (converted into loft apartments), as does the Joplin Union Depot, since railroad restructuring and the decline in passenger traffic led to its closure. Other notable historic structures in Joplin include the Carnegie Library, Fred and Red's Diner, the Frisco Depot, the Scottish Rite Cathedral, and the Crystal Cave (filled in and used for a parking lot). The Newman Mercantile Store has been adapted for use as City Hall. The Fox Theatre has been adapted for use as the Central Christian Center.