Chess lessons › Chess strategy
The Carlsbad structure
White’s pawns a2 b2 d4 e3 against c6 d5: both sides’ plans, with the engine.
The idea
White’s a2 b2 d4 e3 against c6 d5: the c-file and e-file decide.
- White has no c-pawn, so a rook on the c-file points at c6.
- Black has no e-pawn, so the e-file points at the pawn on e3.
- White plays e4 or a minority attack; Black plays ...Ne4 or ...c5.
In a game: Look for White pawns on a2, b2, d4 and e3 against Black pawns on c6 and d5, with no c- or e-pawn.
How the lesson begins
You will meet this pawn structure again and again. White’s pawns stand on a2, b2, d4 and e3. Black’s stand on a7, b7, c6 and d5. It comes from the Queen’s Gambit Declined when White takes on d5 and Black recaptures with the e-pawn, and it is called the Carlsbad structure.
Read the files. White has no c-pawn, so the c-file is half-open for White: a rook there points at the pawn on c6. Black has no e-pawn, so the e-file is half-open for Black, and it points at the pawn on e3.
The engine rates the position as close to level. Each side has plans of its own, and the next steps go through them.
A question
Which file is half-open for Black here?
Show the answer
The e-file.
Right. Black has no e-pawn, and White’s pawn on e3 is the pawn that file points at.
In numbers
How often it is played
| Rating | Value |
|---|---|
| Under 800 | Too few games |
| 800 to 1199 | Too few games |
| 1200 to 1599 | 0.7 |
| 1600 to 1999 | 1.8 |
| 2000 and up | 4.6 |
How the games ended
White won 52%, 6% were drawn and Black won 42%, over 2,687 games that start this way, in a sample of rated Lichess games from 2026.