ECO C73: Ruy Lopez

ECO C73 is part of volume C — Open Games. The Lichess chess-openings dataset files 2 named lines under it. The shortest is Ruy Lopez: Morphy Defense, Modern Steinitz Defense: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. Bxc6+ bxc6 6. d4.

That position has come up in 22,050 Lichess games between players rated 1600 to 2500: White won 51.9%, 6.5% were drawn and Black won 41.6%.