Mystic grassy hill north of the Irrsee lake and according to the tradition the resting place of a Celtic prince.
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The Celtic hill is located in the region called "Gegend" in the district of Oberhofen an is owned by Anna Schindlauer. The mass of the burial mound is more than 3.000 m³. It is evidence of Celtic ancestors in Oberhofen.

In 1985 the mountain unversity of Leoben conducted geophysical surveys. In the centre, at a depth of 6m, a larger excavation-damaged zone resulting from a broken burial chamber has been found. This is undoubtedly the largest burial mound in Austria. The only other Celtic burial ground of a similar size can be found in Großmugl, Lower Austria.

A wooden cross or stone monument would have stood on top of the grave. The former owner, Franz Schindlauer, made several applications to the "monument" departement of the Austrian Federal Office for the Care of Monument (Bundesdenkmalamt) to lift the so-called Keltenhügel. However the Bundesdenkmalamt rejected the applications. Once the measurements had confirmed this, the hill was placed under protection because the opening of the grave would and had never been placed under monument preservation in the archeaological sense.

The Celtic hill is to remain in its entirety as a monument for future generations. According to legend, the prince of the neighbouring settlement is buried here sitting on a steed with all of his belongings.
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