Hesse or Hessia, officially the State of Hessen, is a state in Germany. Its capital city is Wiesbaden, and the largest urban area is Frankfurt. Two other major historic cities are Darmstadt and Kassel. With an area of 21,114.73 square kilometers and a population of just over six million, it ranks seventh and fifth, respectively, among the sixteen German states. Frankfurt Rhine-Main, Germany's second-largest metropolitan area, is mainly located in Hesse.
As a cultural region, Hesse also includes the area known as Rheinhessen (Rheinhessen) in the neighbouring state of Rhineland-Palatinate.