Addender

The aliens will live in different regions of the same planets. Thus will coexistence flourish, and when plagues break out, each species will bring in doctors and nurses from an immune species.

Addendum

The same won't be true of the other planets we will undoubtedly colonize because far smaller regions will be inhabited. When you can pick and choose the best places, you don't want to leave anyway.

Earth's Future

Canals everywhere. Every continent divided into even grids by canals. Cars: Obsolete. Trains: Obsolete. Planes: Rigged for water landings. Bicycles: Retained for health reasons only. Motorcycles: I'm pretty sure they're used to annoy everybody even today, so nothing will change there.

Addendum

That aside, the future will almost certainly have either trains or the apocalypse. Possibly both.

Science Fiction Logistics Considerations

When considering whether your setting's transportation has developed to such a level that there are no longer surface trains, remember that people can grab on to the sides and shoot bandits or else have tense fights on the top.