Simplify the following text for a Grade 5 native English-speaking person.
Original: The river is formed by the confluence , near Colditz , of the Zwickauer Mulde ( running through Zwickau ) and the Freiberger Mulde ( with Freiberg on its banks ) , both rising from the Ore Mountains .
Simplified: The Mulde is a river in Central Germany . It is formed when the Zwickauer Mulde and the Freiberger Mulde coming from the Erzgebirge meet near Colditz .