Harrison is an 'L' subway station on the CTA's Red Line in the Chicago Loop. The station opened on October 17, 1943, as part of the State Street Subway. In 2006, the KDR standard signage at Harrison was replaced by the newer Current Graphic Standard signage. On February 9, 2009, a new auxiliary entrance at Polk Street was opened due to an increase of both business and residents living in the South Loop neighborhood.