Sondershausen, a town of Germany, capital of the principality of Schwarzburg-Sondershausen, situated in a plain 37 m. by rail N. of Erfurt. Pop. (1905), 73 8 3. It possesses a castle, with natural history and antiquarian collections, and a parish church (restored 1891), with the mausoleum (1892) of the reigning princes. There are manufactures of woollens and pins.