HITZACKER, a town in the Prussian province of Hanover at the influx of the Jeetze into the Elbe, 33 m. E.S.E. of Dine burg by the railway to Wittenberge. Pop. (1925) 823. It has an old castle and other mediaeval remains. There are chalybeate springs in the town. The famous library, originally founded here by Augustus, duke of Brunswick (d. 1666) was removed to Wolfenbiittel in 1643.