In English, we say Once upon a time there was..., but in Spanish, you'd say Había una vez… Fabulous, isn’t it?
We've already seen how to use the imperfect to talk about what you used to do or what you always did.
You can also use the imperfect to say what you were doing!
El rey y la reina caminaban por el bosque.
The king and queen were walking through the woods.