The well house takes the form of a square pavilion with open semi-circular arches at the front and rear. Framed in the arch at the back is the figure of Egeria, executed by Wilhelm Beyer, inclining above a small basin. She holds a vase under her arm from which flows the spring water once so esteemed by the Viennese court. The figure of Egeria is one of the most graceful statues in the park at Schönbrunn. According to legend, the taught the Romans to influence the gods in their favour by performing pious acts in order to ensure the prosperity of the state.
The façade of the small, tempietto-like building is covered in a dripstone-like surface, as is the triangular pediment and the shallow dome crowned with vases, while the architrave is decorated with shells.
The dripstone decoration continues inside the building, and the corners are decorated with sheaves of reeds while garlands of flowers embellish the ceiling. On one of the walls is a stone plaque displaying the crowned initial M, which according to the latest research does not in fact refer to Emperor Matthias and the discovery of the fair spring but to Maximilian II, who acquired the Katterburg estate in 1569.