French Defense: Classical Variation, Frankfurt Variation

The French Defense: Classical Variation, Frankfurt Variation is a chess opening classified under ECO code C13 in the Open Games & French Defense family, beginning with 1.e4 e5 or 1.e4 e6, including the Italian Game, Ruy Lopez, and French Defense. It is reached after 6 moves: 1. e4 e6 2. d4 d5 3. Nc3 Nf6 4. Bg5 Be7 5. e5 Ng8 6. Be3 b6. The resulting position leaves white to move.