Question the first: a confusion as to whether all three of the divine realms (Olympus, Atlantis, the Underworld) could be accessed by any divine road, or if only the road related to the specific realm led there.
Answer: the three roads cross over. That is to say, any world that has open air has the Olympian Road, any world that has underground has the Hadean road, and any world that has rivers, canals or large bodies of water has the Atlantean road. So any normal world might have 'access points' to 1, 2, or all 3 roads.
But you can only get to Olympus by the Olympian road, you can only get to the Underworld by the Hadean road, and you can only get to Atlantis by the Atlantean road. The other two can get you close, maybe, but can't actually ever lead you to the place you seek.
That's what the game originally intended. It means that someone who only has, say, the Atlantean road, can never get to Olympus with it. They need to find another means to get there (usually help from another PC or NPC).
Question the second: How long did you envision it taking to travel from one of the main divine realms to another?
Answer: In general I envision it as normally a trip that (without really stopping anywhere, but not rushing at crazy speed) takes maybe three/four days or so to get from any one major realm to any other IF you know where you're going (otherwise, the first times, it can take a lot longer, like a week or two, because you can't envision where you're going). Likewise, if you are 'hellriding', going as fast as you possibly can, you might be able to get there in two days instead of 3-4.
Also, if you are taking people with you, that also slows you down, so you have to add a few days or even weeks (if you're taking something big, like an army). And all of this assumes nothing interrupts you and you have no difficulties on the trip.
I see the realms as relatively close to one another on the world-scale. On the other hand, I see Modern Earth as being one or two weeks away from any of them; and the really weird worlds (places of crazy physics, ultraweird-fantasy or super-scifi) taking perhaps three or four weeks away from the divine realms, or even further, going out and out until even the laws of time and distance start to make no sense.
(if you want to go here, for some reason, you better pack for a longish trip...)
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