What is Fortress in chess?
A defensive setup where the weaker side builds an impenetrable wall to force a draw despite being down material.
Classic fortresses occur in rook-and-pawn endgames or bishop endgames where the defending king and pawns seal off any entry points. Once a fortress is established, the stronger side cannot make progress regardless of how many extra pieces they have.
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Analyze my games →More chess terms
- Lucena positionThe key winning setup in rook-and-pawn vs rook endgames, solved by 'building a bridge.'
- Philidor positionThe key drawing defense in rook-and-pawn vs rook endgames.
- Key squaresSpecific squares that, once reached by the attacking king, guarantee a pawn promotes.
- TriangulationA king maneuver that loses a tempo to reach the same position with the opponent to move.
- Square of the pawnA visual shortcut to check whether the defending king can catch a passed pawn before it promotes.
- Wrong bishopA bishop that cannot control the pawn's promotion square, turning a winning position into a draw.