The rules on stations are a bit complex. But there is nothing in the rules that either:
- prohibit the use of two or more stations in a single route.
- force the route to have at least one section without a station.
But since each unused station gives 4 points to the end score. And short routes don't give that much points. It is probably only wise to do, if the sections with stations are used with other routes.
Building a train station
A Train Station allows its owner to use one,
and only one, of the routes belonging to another player, into (or
out of) that city to help him connect the cities on his
Destination Tickets.
So you can use stations to borrow a route from another player. Each station borrows only a single route.
Stations may be built on any unoccupied city,
even if it currently has no claimed routes into it.
This is a bit vague, but later on, it implies, you can build a station on an unoccupied city and in the end chose one of the routes (taken by another player) to claim.
Two players may never build a Station in the same city. Each player may build a maximum of one Station per turn, and three Stations through- out the
course of the game.
(Skipped part on using cards to pay for stations)
If a player uses the same Station to help connect cities
on several different Tickets, he must use the same route into the city
with the Station for all of those Tickets. The Train Station owner
does not need to decide which route he will use until the end of the
game.
So it can be an advantage to claim a city using a station to avoid a later clogged bottleneck. Which also implies only one station can be build on a single route. (It does not solve the situation in which two players each claim a different city on the same route...).
A player is never required to build any Stations. For each
Station a player has not used, four points are added to his score at
the end of the game.
