No, its not about plot.
An actual magical version of a railroad.
First off, teleportation and similar spells are limited to specific points on the map. They have only recently been "unlocked." I was considering using dimension door in a series of gateways along a track that a carriage travels on.
Does this sound dumb? Can it be worked with?
There are already ring gates, which could theoretically be made larger. With a range of 100 miles, a "road" can be created by placing a pair of gates at intervals. If you can walk through them, rings 6'-8' in diameter, with at least that distance between pairs could make for an interesting bit of travel.
I'd suggest working something into the design which would prevent the rings from being moved, and thus hijacking the road, and each stop should have some means of preventing anything from blocking or hindering passage, such as guards or a spell with constantly removes debris from between the gates. Placing the gates inside buildings could help protect travelers from the elements and hazards of weather.
No, I don't think it is not dumb. I had a world I created where teleportation was not available. The way around this was ley lines of magic that ran in different patterns around the continent and world. All Teleportation was only available through these paths. Naturally major cities developed on these lines and a mages guild constructed (for lack of a better example) Stargate like portals. For a fee they would teleport people, goods, and stuff like that to other cities.
I created a formula that player arcane casters can add their level and ability modifier times 10. If they were within this distance, in miles, of a ley line they could tap into it and use the residual magic emanating from it to teleport or Dimension Door.
Dimension Door was the only way to avoid using a gate as an exist, but that is why it's distance is limited. But Teleport - you had to exist a portal and pay the fines for not using the Mages Guild services - per person.
Oh and the clerical spell Word of Recall was a closely guarded secret by the clergy as this bypassed the Ley Lines. This world history had some bad blood between the arcane and divine powers. Naturally, this idea was when Stargate the movie and series was just kicking off.
Ring gates sound cool, though I may have a rule where they must be in sight of each other or something to work. I want to still give the illusion of a track. As far as security, should there be physical guards? Would conjured guardians work? What about protection against an enemy antimagic field?
each station is a set of twin arches spaced a few dozen feet apart. Each station is within sight of the next down the line. I can post a pic if the map to see where things might take shape...
I used to have permanently animated wagons and carriages. Since, they don't really have intelligence scores I only allowed them to follow a pre-made route, but they never attacked or stopped. You could always do a similar thing, but just have them fun on a track with pretty much a go, stop, and reverse command.