The Noah's Ark Trap is a family of traps in the Ruy Lopez chess opening in which a white bishop is trapped on the b3-square by black pawns. The origin of the name is uncertain. The shape of the black pawns on a6, b5, and c4 may resemble an ark, or the name may suggest that the trap is "as old as Noah's Ark".

The trap

Chess masters have occasionally fallen victim to this trap. An example is a game between Endre Steiner and José Capablanca at the Budapest tournament in 1929: Better moves for White are 5.c3, 5.Bxc6+, and 5.0-0. Alexander Alekhine recommended this move in the tournament book for New York 1924 as a means for White to draw, but it is a mistake that loses. White should instead play 8.Bd5 or try a gambit with 8.c3. The white is trapped. White resigned after 32 moves.

In the Sicilian

A variation of this trap can occur in the Sicilian Defence after the moves '''1. e4 c5 2. Nf3 Nc6 3. Bb5** (the Rossolimo Variation) 3... a6 4. Ba4?? (4.Bxc6 is necessary and is the point of 3.Bb5) **4... b5 5. Bb3 c4''' (see diagram). The bishop is similarly trapped.