For first edition rules follow here: River.
General info and comments
The River II was released for the New Edition by Hans im Glück in 2017 as part of Count, King and Robber. The River II was originally released for the 1st. Edition in 2005, and later bundled in the major expansion Count, King and Robber in 2008.
The river expansions modify the beginning of the game by having players place a set of specific river tiles before the normal tiles.
- The River: 12 river tiles, each with a dark back and no symbol (original version) or a stream symbol (Big Box 6 version).
- The River II: 12 river tiles, each with a dark back and a crown symbol.
- The 20th Anniversary River: 17 river tiles, each with a dark back and no symbol. One of the tiles is double-sized.
- The River C3: 12 river tiles, each with a dark back and no symbol (both the base game version and the Big Box 7 version).
- CutCassonne: 3 cut-n-play river tiles with no symbol.
The river expansions replace the start tile. Select the river expansion you want and discard the others. However, you may combine The River and The River II as indicated below.
Preparation of The River (New Edition and C3)
Set aside the source and lake tiles. Shuffle the remaining river tiles and stack them facedown. Add the lake tile to the bottom of the stack, and place the source tile faceup as the starting tile.
The same rules apply to The River C3, even if its source and lake tiles are slightly different:
Preparation of The River II
The river expansion added to Count, King and Robber includes a river fork tile. It should be set aside along with the source and lake tiles. The fork tile is to be placed first (after the source tile) by the first player. 
Combining The River and The River II
You can combine The River from base game with The River II to make a very long river. Keep only one source and one lake.
Preparation of the 20th Anniversary River
Set aside the double-sized source and the two lake tiles. Shuffle the remaining river tiles and stack them facedown. Add the two lake tiles in random order to the bottom of the stack, and place the source tile faceup as the starting tile.
The River II special features
The inn and the volcano on the river follow the rules from their expansions (Exp. 1 - Inns and Cathedrals and Exp. 3 - The Princess and the Dragon, respectively). The pig-herd  has the same effect as a pig in a field (from Exp. 2 - Traders and Builders). If you are playing without any of these expansions, simply ignore their associated features.
Clarifications for new landscape tiles
When placing meeples and scoring fields bear in mind that river segments split fields. 
The following tiles do not split fields - there is one field on each tile 
Fields do not go under small bridges - there are 4 separate fields here
and three fields here, one north and two south.
This large bridge does not separate fields. There are two fields here - one eastward and one westward. 
The houses by this bridge do not end the road.
For the River II there are some clarifications when using it with other expansions:
- Exp. 1 - Inns and Cathedrals: One of the river tiles contains an inn that affects a road.
- Exp. 2 - Traders and Builders: The pig-herd increases the value of its field by 1 point per completed city and castle. This bonus is in addition to the points given by the pig. 
- Exp. 3 - The Princess and the Dragon: Immediately after placing the lake with volcano, place the dragon on it.
- Exp. 5 - Abbey & Mayor: The pig-herd only affects field scoring for farmers during the game (due to the barn) and after the game. Barns do not score additional points from the pig-herd after the game.  
- Exp. 6 - Count, King & Robber: We recommend not to use a river and The Count of Carcassonne. Combining the two can lead to situations where the river cannot be completed.
- Note: If you decide to use The Count of Carcassonne and a river as starting tiles for a game, it is possible that one will not be able to use all of the river tiles if they are placed too close to the City of Carcassonne. River tiles which cannot be placed should be removed from the game, in accordance with the basic rules. Even if the river cannot be placed in its entirety, the game should proceed in the usual way.
House rules for The River
- You are not permitted to lay down any meeples until the entire river is down. (Thanks to metoth)
- Once the river is complete, it may be moved to the center of the playing area. (Thanks to Joff)
- Instead of starting with the spring and setting aside the lake, put all of the river pieces into the bag. In this way the river can be any size and there is usually more then one option for placing a river tile. (Thanks to DavidP)
- Mix the original starting tile (without a river) in with the river tiles. If it is drawn then it acts like a 'bonus' tile that can be placed anywhere. (Thanks to RationalLemming)
- Lay the river in reverse order, from lake to spring. No real advantage, but might be more desirable, when playing the Count of Carcassonne expansion, to have the lake near the City of Carcassonne for purely aesthetic reasons. (Thanks to Scott)
House rules for The River II
- Play the fork of the river first, and lay the spring last. The lakes are mixed in with the other river tiles. (Thanks to Joff)
- Pig-herd tiles do not score a bonus. (Thanks to Joff)
- Play both rivers backwards starting with the city/lake. This is more realistic because you then get two springs producing rivers that join and flow ‘down’ to a lake. Discard two lakes—the plain one from River I and the volcano. To set up, place the lake tile, put one spring tile aside as a final ending tile, and then split the balance of the river tiles into two stacks. The junction tile is shuffled into stack 1 and the other spring into stack 2. Then the stack 1 is placed on stack 2—so that the junction will be drawn sometime before the spring. If playing with the Count of Carcassonne, place the city/lake so that it completes one of the small cities around Carcassonne. (Thanks to dwhitworth)
- Select only one lake tile and use two spring tiles. Lay the river in reverse order. The fork can be placed randomly, or at some predetermined point. The end result is two rivers flowing into one which then flows into a lake. (Thanks to Scott)
- Start from the fork, playing tiles on all three branches. Play the spring and lake tiles at the end, or mix two of the three with the rest of the river before play to have two of the three branches end randomly. (Thanks to Scott)
The River I C3
20th Anniversary River
The River I C2 (Base game version)
The River I C2 (Big Box 6 version)
The River II C2
For Icons explanation and licensing please visit Icons page.
- The HiG rules indicate that the youngest player places the river fork.
- This clarification is included in the HiG rules but omitted by ZMG.
- Note that river segments separate fields. (08/2014)
- This is not standard procedure for placing a volcano tile, according to the rules for The Princess and the Dragon. Under those rules placing a volcano tile does not allow the player to draw a second tile; instead, the player may only perform actions not connected with meeple deployment.
- The English rules called this feature "pigsty." We use pig-herd for consistency with Carcassonne I and also in order to avoid the confusion with the pigsty feature introduced in Carcassonne II, scored by some expansions such as The Markets of Leipzig or The Tollkeepers.
Officially, the field goes around the source, creating a connected field.
This was incorporated in the RGG edition of the Big Box 1, which includes The River (the HiG edition does not) and states that "The field space on the lake and source tiles wraps around those features."
- The city bridge does not separate field segments. Only the river separates the field segments on this tile. Thus, there are 2 field segments on this tile. [This is logical, as similar city bridges in other expansions such as Exp. 5 - Abbey & Mayor do not divide the city underneath. – Chris O.] (1/2013)
- You do receive the bonus from the pig-herd tile even if you don't have a pig on the field. The pig-herd is a neutral pig, so to speak.
- The pig-herd tile can still score an extra point per city when there is a barn on the field.
- There are no official rules for using two pig-herd tiles, as there are no rules for using two copies of The River II, and the similar GQ11 tile is not officially a pig-herd tile (Games Quarterly #11). However, if one field has multiple pig-herd tiles, it seems that they should not stack; in other words, the bonus should only be awarded once, in keeping with other landscape bonuses such as inns and cathedrals.
- This is a general version of a paragraph new in the HiG and RGG editions of Big Box 2, and is rather suggestive for a game of Mega-Carcassonne.