Stephanskloster, Medieval monastery ruins on Michelsberg, Heidelberg, Germany

Stephanskloster is a ruined monastery on the Michelsberg, a 375.5 m hill south of the Heiligenberg in Heidelberg. Only foundation remains and a copy of the Latin-inscribed grave slab of the founder's widow Hazecha survive. The site lies near the university, and stones from the ruins were used in 1885/1886 to build the observation tower on the castle.

The monastery was founded in 1090 as a branch of Lorsch Abbey, growing from a hermit's cell and small chapel. Over the centuries, both Benedictine and Premonstratensian orders inhabited the site before it was eventually abandoned.

The monastery served as a center for learning and spiritual life, and visitors can still trace the community's presence in the surviving foundations today. The ruins reveal how monks conducted their daily routines in this elevated location and dedicated themselves to their work.

The ruins sit atop a hillside with walking paths accessible from the university. A visit works best in clear weather, as paths can become slippery, and the valley views are clearer on sunny days.

After abandonment, local residents received permission in 1589 to quarry the ruins for stone, harvesting materials for other construction projects. Stones from the site were later incorporated into the viewing tower of Heidelberg Castle.