The Hauptplatz, lying on the left bank of the Mur in the middle of the Graz Old Town, is dedicated to the "Styrian prince" Archduke Johann (1782-1859) who did much to encourage industry to come to this backward region and also to improve communications and trade. The fountain shows the Hapsburg surrounded by four female figures. They represent the rivers Mur, Enns, Drava and Sann which flew through Styria in her old boarders.

The architecture of the staggered row of houses in the west of Hauptplatz is suggestive of the Middle Ages. There were the traders displaying their goods below wooden arcades. Masonry arcades can be seen at the two Luegg Houses. Moreover, the Luegg at the corner to Sporgasse is an impressive eye-catcher. In this respect it competes with the town hall dominating the southern part of Hauptplatz.

In 2002, Hauptplatz was redesigned by Graz architect Markus Pernthaler. The wide empty area in front of the town hall offers room. For various events, for instance, promoting public life in the square. Friendly and warm indirect light emphasizes the impressive colourful façades of Hauptplatz at night.