Around 40 theatres are located in Hanover. The Opera House, the Schauspielhaus (Play House), the Ballhofeins, the Ballhofzwei and the Cumberlandsche Galerie belong to the Lower Saxony State Theatre. The Theater am Aegi is Hanover's big theatre for musicals, shows and guest performances. The Neues Theater (New Theatre) is the Boulevard Theatre of Hanover. The Theater für Niedersachsen is another big theatre in Hanover, which also has an own Musical-Company. Some of the most important Musical-Productions are the rock musicals of the German rock musician Heinz Rudolph Kunze, which take place at the Garden-Theatre in the Great Garden.

How many theaters approximately are located in Hanover?