A new soloable game from Friedmann Frise has been announced: Free Ride.
Box cover from BGG
You must connect European cities of the nineteenth century with a railways network. You also move your own train across the network you've built to visit the different cities.
The city of Bremen (picture from BGG)
I'll add more info when it pops up.
That board is nice, actually. Looks like this could be a pretty fun game.