"Any given gate isn't open most of the time. To go through one by accident you'd have to get to exactly the right place at almost exactly the right time. The number if times it's happened probably isn't zero, but the odds are pretty strongly against it happening."
"What would happen if somebody went, could they go back? Are they open both ways?"
"Someone could get stuck if they decided to explore and took long enough that the gate closed, but. It doesn't happen much that people find them by mistake."
"So it's probably not more of a problem than, like, cars."
"I think cars are a good thing to use to figure out how bad a problem is."
"Makes sense. We are even more vanishingly unlikely than most people to get into a car accident, because the velocity of a car is the sort of thing that responds well to light taps of miracle."
Back into Fairyland. The corresponding point in Fairyland is mostly deserted and not also forest (although there are a few earth trees growing nearby, probably from seeds that fell through), so Anaphiel finds a good spot nearby to pitch the tent.
Mehitabel examines an Earth tree. "Do Fairyland plants sometimes come to Earth too?"
"Does the wind blow through portals? Does it make the weather weird?"
"I think portals are generally small enough and temporary enough not to significantly affect weather patterns."
But Mehitabel is more interested in the things that are outside of this tent. "Where are fairies? And unicorns."
Anaphiel does a cocked-head-and-staring-into-space thing that presumably means she is using angelic senses. "There is a herd of domestic unicorns and their herder...far enough off to be significantly inconvenient walking distance. Time for you to learn what teleporting feels like."
It feels like a thing. Like a thing she could do, if she had the practice and the power.
"It felt like a thing I can learn to do that one day I know it."