Waidhofen an der Ybbs (; Central Bavarian: Waidhofn aun da Ybbs) is a statutory city (Statutarstadt) in the Austrian state of Lower Austria. The city had a population of 11,662 (in 131,52 km²) as of the 2001 census. It was first mentioned in 1186 and has been the economic centre of the Ybbstal valley since the 14th century. Sites and attractions Innenstadt: Waidhofen's Old City has many late medieval houses and public buildings enclosed within the old city walls. Several Gothic courtyards and arcades are still present, as are many renovated facades in the Biedermeier, Neo-Renaissance and Neo-Baroque styles. Stadtpfarrkirche: One of Waidhofen's largest and most historic churches, the Stadtpfarrkirche was built between 1470 and 1510. The interior of the church is home to a Gothic winged altar, transplanted to the site from another church in the 1930s. The church's wooden gate dates from the time of original construction. Rothschildschloss: A castle has existed on this site inside the Old City since the twelfth century, although the oldest portions of today's building was built around 1400. The building was home to the region's Bavarian governors out of Freising for centuries and thus the administrative center of the region. The castle is named after the most important former owner, the banker Albert Salomon Anselm Freiherr von Rothschild (1844-1910). An extensive renovation in the late nineteenth century again altered the character of the castle, as did a redesign in 2006/2007 that made use of contrasting modern materials like glass and steel. In 2007, the Rothschildschoss was home to the Lower Austrian Provincial Exhibition and today the castle houses a park, gift shop, and tourism center. The building also houses the 5e-Museum, named after the five elements – fire, water, wood, earth, and metal – that the museum focuses on thematically. During Advent, the castle and its grounds host the town's Christmas market, with crafts, food, punch, music, etc. Once a month during the school year, the castle's interior is transformed into "Crystal Club". Stadtturm (City Tower): This square clock tower is one of the foremost symbols of the city and, at 50 m high, is clearly visible for many miles. It was constructed in the 1530s with the spoils from the expulsion of the invading Turkish hordes. The inscription, dating from 1932, reads "In the year 1532 the citizens, smithies, and farmers of Waidhofen forced the Turkish to flee and built this