Double Fortress

Double Fortress
☖ pieces in hand:
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☗ pieces in hand:
Hifumi Katō vs Sōta Fujii 2016 after 38 moves

The Double Fortress (相矢倉 or 相櫓 aiyagura) is a shogi opening in which both players construct Fortress formations.

Double Fortress games are the most common type of Fortress games found at all levels of play.