Ehrenberg, Mountain summit in Thuringia, Germany.

The Ehrenberg is a 528-metre hill east of Ilmenau and west of Langewiesen in Thuringia, falling steeply about 70 metres to the Ilm to its south. The Ilm breaks out of the Ilmenau basin between it and the Tragberg opposite. Only a small pine grove remains on the summit; the slopes were cleared over the last hundred years, and the western side now holds the Technische Universität Ilmenau campus.

The mountain served as a navigation reference for travelers moving through the Thuringian region during medieval times. This geographical role made it a familiar landmark across many generations.

The summit cross was erected overnight by students of the Catholic student community during the GDR era, and the SED regime never removed it. After weather damage brought it down in 2004, the community renewed it. A memorial stone at the Knebelblick recalls the poet Karl Ludwig von Knebel, who liked to linger here at sunset in the 18th and 19th centuries.

The summit lies on the border between Ilmenau and Langewiesen, about 500 metres north of the Ilm, to which the slope drops roughly 70 metres. The west side is occupied by the Hans-Stamm-Campus of the Technische Universität Ilmenau, named in 1998, whose first buildings went up in 1955 under rector Hans Stamm. The Informationstechnikzentrum Bund and the Werner-von-Siemens-Straße and Ehrenberg Ost commercial areas also sit on the hill.

The Ehrenberg's rock contains hydrobiotite, a mineral also called voigtite, noted in geological descriptions of the hill. On the summit stands a wooden cross put up by students of the Catholic student community during the DDR era; the SED regime never removed it. Weather damage brought it down in 2004, and the community renewed it.