The exact extent of the passageways is still not known with any great certainty, despite investigations commissioned by the town, but the length is estimated to be at least 40 km. Guided tours through this unique underground labyrinth are offered all year round by the town's Tourism and Festival Play Bureau. There are also town tours and night watchman tours. Theatre Annually, between August and October, the Oppenheimer Theaterfestspiele (“Oppenheim Theatre Festival Plays”) take place in the town's Kulturkeller (“Culture Cellar”) and at Landskron Castle's ruins. Museums Particularly worth visiting, besides Saint Katherine's Church, the Town Museum and the underground labyrinth, is the German Viticultural Museum (Deutsches Weinbaumuseum) with the region's oldest wine press from the Geistermühle, a centuries-old mill in Flonheim. Everything worth knowing about wine can be found here. Music In the Kultursommer (“Cultural Summer”), there are regular concerts in the town's historic marketplace in front of the Town Hall. The Oppenheim Trombone Choir also gives regular performances. Sport There are several sport clubs in Oppenheim, e.g., TC Rot-Weiß Oppenheim (Red-White Tennis Club) (tennis), FSV Oppenheim (Football Sport-Verein) (football), and one founded in 1846 that may well have the most members, TV Oppenheim. TV (Turn-Verein= gymnastics and sports association) Oppenheim is successful well beyond its home region in gymnastics, swimming, cycling sports and above all, basketball. Regular events Each year in the town at Landskron Castle's ruins, Saint Katherine's Church, the Kulturkeller under the courthouse square and the marketplace, the Festspiele Oppenheim (“Oppenheim Festival Plays”) take place. An Easter Market also takes place annually early in the year and later in the year, the Saint Katherine's Market in the Old Town. Other regular events in town are: The Easter Artists’ Market (Osterkünstlermarkt), a fortnight before Easter; The well-known and well-loved Oppenheim Wine Festival (Oppenheimer Weinfest) during the second weekend of August; Mittelalterspectaculum (“Mediaeval Spectacle”) in early May; Rhine Bicycle Ride between Worms and Oppenheim in mid-May; Fairytale Christmas Market (Märchenweihnachtsmarkt) at the historic Town Hall, Saint Katherine's Church and the marketplace on the third Sunday of Advent. Economy and infrastructure Public institutions The administration of the Verbandsgemeinde of Nierstein-Oppenheim is based in Oppenheim. The State Office for Environment, Water Management and Trade Control, the Mannheim Water and Shipping Office and Mainz-Bingen District Vehicle Licensing are all located town. Education Besides three kindergarten institutions or kindergartens (of which two are municipal daycare centres), there is the “Am Gautor” primary