Sixty-six or 66 (German: Sechsundsechzig), sometimes known as Paderbörnern,[a] is a fast 5- or 6-card point-trick game of the marriage type for 2–4 players, played with 24 cards.

[1] Closely related games for various numbers of players are popular all over Europe and include Austria's national card game, Schnapsen, the Czech/Slovak Mariáš, Hungarian Ulti, Finnish Marjapussi and French Bezique.

[2] The ancestor of sixty-six is the German game of Mariage, which was first recorded in 1715 under the name Mariagen-Spiel[3] "despite claims for its invention at Paderborn, Westphalia, in 1652".

[1] Although there is a commemorative plaque in Paderborn at Kamp 17 stating that the "world famous game of Sixty-Six was invented here in the pub at No.

[5] Sixty-six appeared in German card game compendia as a variant of Mariage around 1860, the main differences being that it was played with 24, not 32, cards, the bonuses for amour (holding the trump Ace and Ten in the hand) and whitewashing (taking all six last tricks) were dropped, and players could 'go out' on reaching 66 without playing to the end (whereupon the winner of the last trick won the game regardless).

[7] In 1901, sixty-six was reported to be one of the most popular penny ante games in the city of Pforzheim in Baden alongside Cego, Skat, Tapp and Tarrock (possibly Dreierles).

[8] Sixty-six was widely played by Polish Americans in South Bend, Indiana, in the 1950s and '60s.

In the 1970s and '80s, a more aggressive bidding approach was developed in familial games known as the Kromkowski style.

[9][c] Sixty-six is a 6-card game played with a deck of 24 cards consisting of the ace, ten, king, queen, jack, and nine, worth 11, 10, 4, 3, 2 and 0 card-points, respectively (by comparison, its close cousin, the Austrian game of Schnapsen does not make use of the nines and has a hand size of 5 cards).

Players must remember how many points they have taken since their scores may not be recorded, and they are not allowed to look back at previous tricks.

Once the trick is played, the winner takes the top card of the talon to replenish his hand, then the loser does the same.

On his turn when he has the lead, a player may meld a queen–king 'marriage' or an Ober–Unter 'pair' of the same suit by playing one and simultaneously showing the other.

A marriage or pair is usually announced in some way to the other player, often by saying the number of points made ("twenty" or "forty").

Once the talon is gone, with the turned up trump taken by the loser of the sixth trick, the rules of play change to become more strict.

Closing indicates that the closer has a good enough hand to reach the 66-point target under the stock-depleted rules above.

The stock is now "closed" and players do not replenish their hands, and there is no 10-point bonus for taking the last trick.

The Austrian national two-handed variation of sixty-six in which all the nines are removed for a 20- rather than a 24-card deck, and the hand size is reduced from six to five cards.

It is regarded as a very strategic game, and articles and books have been written about winning strategy.

[11][12] North-American sixty-six is also a partnership game which uses a 24-card pack ranking 9, 10, jack, queen, king, and ace.

In Polish American communities of South Bend, Indiana, the game is played to 15, so a 7 and 8 are used for scoring.

Since then, innovations were made using aggressive bidding, notable in South Bend, Indiana.

Consequently, players were not able to work out the optimal odds and circumstances favoring a more aggressive bidding style which was allowed in family friendly games where younger players were free to push the boundaries without fear of losing money (or card room brawls.

If the player does not have the led suit or trump, his partner is free to play any of the remaining cards.