In 1129, Margrave Leopold I of Steyr founded Rein Abbey (Lat. runa). The monastery site in the Gratweiner Basin, in the almost untouched valley of the Mur, surrounded by wooded mountainous land, offered the monks called from the monastery ebrach (Franken) good conditions to build a monastery in seclusion and asceticism.
Of particular importance for the supply of the monastery and thus for the work in the landscape were silvicultural, wine growing and salt mining. In the first decades after the foundation of the monastery, the monks themselves were involved in the extraction of salt and operated a salt tunnel in Altaussee. From the 13th century onwards, the pen continued to receive a fixed amount of salt, which flowed into both its own use and trade. It is highly likely that the mother monastery of Ebrach also received salt from Rein.
The early collapse of the conversentum in Rein had the dissolution of most Grangien, so that they almost disappeared from the landscape.
The lively trade of the Reiner, which was developed in the early 14th century, can be seen as a special feature of this abbey and is still visible today in its representative city courtyards in Graz and Hartberg.
In addition to the sale of wood and salt, the Stift Rein received the highest income from the sale of wine. At the beginning of the 14th century, the income from the wine trade represented about a third, and in the middle of the 15th century even the majority of the total revenue.
Typical traces of this use have been preserved in the landscape: terraced southern slopes for viticulture, ponds and pond chains for fish farming, as well as the hydraulic system of the monastery complex and its farm, which are over the moat from the Mühlbach valley were fed.
The large monastery forest and the numerous mills along the rivers are still important distinguishing features of the monastic cultural landscape.
The abbey itself in its baroque appearance of the 18th century and the Gothic pilgrimage church of St. Mary in Strassegel set visible accents in the Gratweiner landscape. Stift Rein is today the oldest uninterrupted Cistercian monastery in the world.