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Photo: AleXXw, Public domain via Wikimedia Commons
These lakes are the remainders of an abandoned gravel mine. As there exists suitable infrastructure (public transport, pubs) it is a nice place to hang out. Boats are available to rent.
© OpenStreetMap contributors
Diözesanmuseum
Displays religious art and artifacts, from the Middle Ages until the current era.
Located within the state parliament building (Landhaus), this gallery houses rotating exhibits of contemporary art by Lower Austrians.
Ehemalige Synagoge
The Jugendstil synagogue was designed by the architects Theodor Schreier and Viktor Postelberg, and built in 1913. The building was severely damaged during the Kristallnacht in 1938; after 1945 administration of the building was given to the Jewish community of Vienna, as the Jewish community of St. Pölten no longer existed. In 1980 a comprehensive restoration project was commenced; the only portions of the building which could not be reconstructed were the Hebrew verses in the medallions and the Jugendstil glass windows. Today the building is a memorial, and used by the surviving Jewish community for special events.
Tower of Sounds
Designed by the architect DI Ernst Hoffmann and built in 1996, this is a nice place to get a view of the city from above. Sometimes there are exhibitions in the so called "Klangkugeln" (sound spheres) which are worth a visit.
A concert hall and staged, designed by the Austrian architect Klaus Kada and opened in 1997.