[Edi]

Forgot about astral window, and I don't know if domes stop site searching spells. I suppose domes affect spells that try to do something that actually interacts with a province or the units and commanders in it as opposed to doing passive things (like Astral Window). So trying to spell-drop an army in, toss assassination spells like Seeking Arrow or snatch a commander via Winged Monkeys and whatnot would get bounced off the dome.