Nykvarn is a locality and the seat of Nykvarn Municipality, Stockholm County, Sweden with 7,560 inhabitants in 2017. Between 1971-1998 it was a part of Södertälje Municipality. Nykvarn is the hometown of such bands as Hyena Breed, Feed Filiph, From Zero to Hero and Aldiureep, as well as Stanley Cup winner Carl Hagelin. The city hosts the annual rock and metal festival called Moshpit Open Festival.