Desciption from App Store:
Implements the France part of the Ticket to Ride Map Collection: Volume 6 – France & Old West.
2-5 players collect train cards and claim routes in order to complete tickets in hand, but most of the tracks on the board aren't colored! Each time that you draw cards, you must take a colored tile that's 2-5 train cars long and place that tile on an empty track bed. Once you've done this, any player can claim that route by discarding the appropriately colored cards from hand, as in any other Ticket to Ride game. (Single-length routes are already colored, and the map contains a number of gray-colored ferry routes.)
Multiple track beds on the game board overlap, and once a tile has placed on the board, any track beds crossed by this tile are off-limits and nothing can be built on them. At the end of the game, players score their tickets, with bonuses being awarded for longest continuous route and most tickets completed. (Taken from BGG description of the expansion.)