GELNHAUSEN, a town in the Prussian province of Hesse Nassau, on the Kinzig, 27 m. E.N.E. of Frankfort-on-Main, on the railway to Bebra. Pop. 4,838. Gelnhausen became an imperial town in 1169, and here diets of the Empire were fre quently held. In 1803 the town became the property of Hesse Cassel, and in 1866 passed to Prussia. It is still surrounded by ancient walls and towers. On an island in the river are ruins of the palace built by Frederick I. (Barbarossa) before 1170, and destroyed by the Swedes in the Thirty Years' War. The beauti ful Marien Kirche, with four spires (of which that on the transept is curiously crooked), was built in the 13th century, and restored in 1876-79; among other ancient buildings are the town-hall, the Fiirstenhof (now administrative offices), and the Hexenthurm. Indian-rubber goods and brushes are manufactured.