I would go in between the crown and the ceiling. Because of the size of the crown you may need an extended rod to clear the crown.

If you need light blocking you might have to add a blind as well.

Keep in mind that unless you are using custom you'll have to work with available lengths. You can add a couple of inches of length if you use curtain rings.

That's not crown when it's a detail for your window. I would not hang curtains, I would select something that fits inside the frame of the window like a shade or blinds.

Thank you! We're pretty set on curtains :) We do have a curtain rod with an extender so we should be able to hang it further out. We'll probably add a black out blind in the kids' room (so we all get some sleep!)

Crown molding is the molding on top of the wall under the ceiling. Anyways, 6" is plenty of space to mount a rod. 3" is all that's needed to clear the molding on top of the window, so you can mount it anywhere 3" or higher.

Yes, newbie here.... I meant trim not crown moulding!