Schloss Arenfels was built as a
fortress in 1258-59 in
Bad Hönningen,
Germany along the
Rhine River. It was built by
landgrave Gerlach von Isenburg. In the 17th century it was turned into a
Renaissance Palace, and in 1849 was renovated in a Neo-
Gothic style by
Ernst Friedrich Zwirner. In that same year it was acquired by the
Count of Westerholt-Gysenberg. Today it is the location of the Cafe-Terrasse, which offers wine tastings and dining in the castle's old Knights Hall.
http://www.general-anzeiger-bonn.de/freizeit/sehenswertes/schloss_arenfels.html
http://www.bad-hoenningen-rhein.de/stadt/schloss/