Le Tunnel (première édition)
Spielbox Issue 6 2009
Informations générales et commentaires
- 4 tuiles Terrain
- 12 jetons Tunnel, deux jetons en six couleurs
Mise en place
The four land tiles are mixed with those of the basic game. Every player receives the tunnel tokens corresponding to his or her color. In games of two, each player may use three sets of tokens; in games with three players, each may use two sets. 
All the rules of the basic game apply, with the following additions.
Déroulement d’une partie
Revendiquer des tunnels avec des jetons
During his or her turn,  a player may place one of his or her tunnel tokens on any currently unclaimed  tunnel opening, including on the land tile which has just been placed. Independent of this, the rules for deploying a follower remain the same. 
Quand est-ce qu’un tunnel est terminé ?
As long as there is no tunnel token claiming a tunnel opening, the road leading to it is "broken off," without being complete.  The road remains incomplete even when a tunnel token is placed on the tile. Only when the second tunnel token of the same color is placed on another unclaimed tunnel opening (which may or may not be on the same tile) are the tunnel "entrance" and "exit" defined, and the tunnel finished.  The road then runs underground through the tunnel, but is not completed at the tunnel exit. The road is completed in the usual way, such as by reaching a crossing.
The color of the tunnel tokens is only important for linking two tunnel openings. Indeed, the tunnel is built for everyone; for example, a thief of another color can score a road which goes through a finished tunnel. In extreme cases, a road may lead underground several times in a row. 
After scoring, the tunnel tokens remain where they are, so that at most five tunnels (or six with tunnels from other expansions) can be built.
Take care with the tiles shown beneath. 
Players may use tunnels in a cutthroat way to make a road impossible to complete and trap all the followers on it for the rest of the game: a player may lead to this situation by claiming a tunnel opening with a token and never placing the second token. This possibility has generated much debate.
In order to mitigate this situation, some variants have been suggested: 
- You are only allowed to place a tunnel token on a tunnel opening if at least 1 of your followers is placed on the road connected to that tunnel. (Thanks to Player77)
- The affected player is allowed to steal the 2nd tunnel token and place it immediately during their turn, if the token's owner did not use at least one opportunity to place it. (Thanks to Christwart Conrand, creator of the expansion)
- Both tunnel tokens must be placed at the same time when road with a tunnel is occupied by a player. Moreover, tunnel tokens should not be player-specific. (Thanks to Whaleyland)
- Players cannot use a tunnel token to block an opponent's follower. (Thanks to corinthiens13)
Interactions avec les autres extensions
This section contains additional information about the interactions with other Carcassonne expansions.
Ensemble des tuiles
Pour les licences et les explications des icônes, veuillez visiter la page des icônes.
- Pour Le Tunnel, nous disposons de trois ensembles de règles : celles publiées à l’origine dans le magazine Spielbox, celles sur le site de Hans im Glück et, à partir de celles-ci, une traduction anglaise sur le site de Spielbox. Nous avons utilisé les règles de Hans im Glück comme base, mais nous signalerons les différences entre les versions si nécessaire.
- The rules published in Spielbox say that in games of two, each may take two sets of chips.
- A specific time during the turn is not stated, indicating that the token can be placed at any time during the turn. (10/2014)
- The rules say "unoccupied", but we feel it is worth making a distinction between occupying (with a meeple) and claiming (with a token).
- This last sentence does not occur in the published Spielbox; it clarifies that a player may both deploy a follower and place a tunnel token in the same turn.
- This and the next section are greatly revised from the rules published in Spielbox, clarifying a number of issues.
- The rules only mention that the tunnel entrance and exit are "defined" but we feel it is worth making a distinction between a road being completed, and a tunnel being finished. The Spielbox English translation does not, and is potentially confusing.
- The Spielbox English rules add that a road may "[pass] behind other roads underground." We are inclined to think that this is a mistranslation of "hintereinander," or "in a row."
- It would seem logical that if the "entrance" and "exit" of a tunnel are on the same tile, they should only count as a single point for scoring, just as two segments of a city on a single tile only count as 1 tile for scoring purposes.
- Although not specifically stated, the finished road with tunnel tokens is scored during the normal scoring phase, as the rules do not indicate anything to the contrary. (10/2014)
This clarification was confirmed by Christwart Conrad, the author of the expansion. He confirmed the RRRR tile has 3 field segments.
He also provided a link to BGG discussing the fields on the four tiles.
The first two variants were discussed on two consecutive posts available on BGG:
The remaining variants where discussed on several posts on Carcassonne Central (replies #2 and #10):