The Zeiss-Planetarium in Jena, Germany, is the oldest continuously operating planetarium in the world.
Engineered by German engineer Walther Bauersfeld, the building was opened on 18 July 1926.
The Zeiss-Planetarium is a projection planetarium; the planets and fixed stars are projected onto the inner surface of a white cupola.
It is owned and operated by the Ernst-Abbe-Stiftung.