D&D General Good Golden Vault Adventures?

[pukunui]

They don't run the lightning rail though.

That’s true. It could be a Daanvian lightning rail rather than a House Orien one.

And a train between Eberron's Moons/Planes doesn't seem like a good fit lorewise or tonally.

And each carriage on the Concordant Express is a kind of planar vignette. No problem mechanically, but you lose a lot of the sense of it without Planescape lore.

@Zardnaar: I’ve found this to be a useful resource for running Golden Vault adventures in Eberron: Eberron: Keys from the Golden Vault - Dungeon Masters Guild | Dungeon Masters Guild

For the Concordant Express adventure, one suggestion involves an experimental lightning rail that passes through Khyber (including several demiplanes). The other suggestion is to have it be a modron train that travels through multiple planes before reaching Daanvi.

 

[Paul Farquhar]

an experimental lightning rail that passes through Knyber

I feel that should be more like Event Horizon than Time Bandits!

 

[pukunui]

I feel that should be more like Event Horizon than Time Bandits!

Yes. LOL.