The ruins of Fragenstein castle are a great panoramic hiking destination and a historic reminder of the Middle Ages. The origin of the castle is the source of many mysterious stories and the exact date of construction is still unknown. Historians believe that the castle was built by the Counts of Andechs in the early 12th century, while others attribute it to the Counts of Gorizia.
(https://www.innsbruck.info/en/regions/neighbouring-villages/zirl/fragenstein.html)