In 1170, Emperor Friedrich II Barbarossa founded the city of Gelnhausen and at the same time, began construction of a palace below the city on the wetlands of the Kinzig River. Ten years later, it was completed and ultimately served on several occasions as a stage for imperial diets. It is surrounded by a sweeping circular wall whose irregular shape corresponds to the flow of the Kinzig. Its high masonry, which extends up to six meters, consists of rusticated stones at its exterior which give it a challenging and well-fortified appearance. By contrast, the interior architecture conveys imperial power through its variety and artistic embellishment. Upon entering, a vaulted entryway opens into two wide arches upon a large inner courtyard; the capital with four eagles in front of the middle column refers to imperial honor. From the entryway, steps lead to the overlying chapel and laterally connecting, formerly three-storied great hall. From this, the imperial great hall, the lower floors of the court façade and a section of the rear wall have been preserved. The façade is richly divided by arcades that are supported by double rows of columns. Their capitals are articulated in great detail, as are the trefoil arch above the portal and the fireplace located on the other side of the interior wall which once heated one of the halls. In the entryway are more richly-decorated pillars and stone sculptures which came from the great hall and symbolize imperial power. South of the entryway is the gate tower, or Torturm, which was conceived as a final escape in the event of conquest and was therefore built from rusticated stones in the manner of the surrounding wall. Although originally markedly higher, it now offers from its modern platform a far-reaching view of the Kinzig valley and city of Gelnhausen.