Windsor Park Mall was a shopping mall located on the northeast side of San Antonio, Texas, off Interstate 35 and Walzem Road. It opened in 1976 and closed in 2005. In 2007, the building, of which ownership was transferred to the suburb of Windcrest, Texas, became the new corporate headquarters of Rackspace, a Web hosting company. Their redevelopment of the mall structure, now known as "The Castle", has sparked a redevelopment of the surrounding area.