The Greiner Planet Trail "Jupiter" is an impressive project initiated by the scientist Werner Riegler, a native of Greiner. Riegler is a senior scientist at the Cern research centre in Switzerland. This extraordinary planetary trail stretches along the banks of the Danube over a total distance of 1.6 kilometres. A special feature of this project is that the distances of the planets from the sun and their sizes are shown on a scale of 1:2.8 billion. This results in an impressive distance of 1.6 kilometres between the sun and Neptune, while the diameter of the sun along the way is 50 centimetres and that of the earth 4.6 millimetres.

The models of the planets are mounted in glass cubes with 3D laser engraving and are illuminated from the inside to emphasise their details. The positions of the planets along the path are carefully planned: The sun and the planets Mercury, Venus, Earth and Mars are placed between the mouth of the Greinerbach stream and the Schinackl restaurant. Jupiter is already at the level of Konditorei Schörgi, while Saturn has its place on Esperanto Square. Uranus is positioned below the Hofer market and Neptune near the Danube bridge.