The basilica lies at the wooded back of the Manhartsberg mountain. The church is one of the most beautiful pilgrimage churches in Austria and is decorated with the last work by Paul Troger - a large dome fresco.
In 1656 the furrier Matthias Weinberger from Horn erected a waxen pietá at the roots of an oak at the Moder Berg mountain, after he had recovered from a lingering illness and had followed the instructions he received in one of his dreams. 20 years later the tree burnt down, the waxen pietá melted. Horn's mayor S. Friedrich had a sculpture erected, which was made by the sculptor Sturmberger - today's image of grace. Placidus Much, the great baroque abbot of the Stift Altenburg, engaged the master builder Leopold Wißgrill from 1744 to erect today's structure of the church, which could only be finished with the towers in 1818. The organ of the Viennese master Anton Pfliegler still has its old interior, which produces tones of rare beauty (1789).
Thomas Friedrich Gedon, one of Daniel Grans' disciples, Bergl and the Kremser Schmidt created the church's altarpieces. The central point of the high altar is the statue of grace, which is rather plain compared to the great number of excellent pieces of art. Behind the high altar one can still see the black roots of the oak. The treasure chamber also shows the pilgrims' godly trust in the intercession today.