Midvale is a small metropolis suburb which was the home of Silver Age Supergirl. After arriving on Earth Superman encourages Kara to take the name Linda, don a disguise and live in the Midvale Orphanage. She was never to let anyone know of her powers. Kara would do as she was told but at night she would protect Midvale as Supergirl.
In the 'Supergirl' movie Midvale Orphanage becomes Midvale Boarding School where Kara meets Lucy Lane. Most of the movie takes place in the small town.