I was thinking of a place where technology failed, possibly as a result of a colony way out there, large enough to have a remnant population survive and then repopulate - without tech, and find that there's (rather rarely) magic. Oh, and there're odd metal things, look vaguely like a sailing ship, up in the sky, which look like they've been shot at - and odd ruins with unknown, hard, non-metal non-rock, very smooth things with glass parts in them...