What is "ferropolis"

Ferropolis, "the city of iron" is an open museum of old huge industrial machines in Gräfenhainichen, a city between Wittenberg and Dessau, Germany. It's an open-air museum which contains machines from the mid-twentieth century. They can measure to 30 meters high, 120 meters long and weigh up to 1980 tons. Moreover, the area is used for several events like opera or music festivals like the Splash! Festival, Melt! Festival and the "Ferropolis in Flammen" ("Ferropolis in flames").