Open file: a clear road for the rooks

In short

Look along a file from bottom to top. If there is no pawn on it, it is called an open file. A rook can travel a long way along it as long as no piece blocks its path.

Nimzowitsch already counts a file as open when only your own pawn is missing from it. An enemy pawn may still stand on it; it is then a target or an obstacle. Today such a file is usually called half-open.

A file opens when one of your own pawns disappears. Often your opponent exchanges off a piece that stands well in the centre, and a pawn recaptures. You can also send a pawn forward against an enemy pawn and exchange. Nimzowitsch, using a word of Tarrasch’s, calls this enemy pawn the point of attack.

The goal is to break into the seventh or eighth rank, and to do so along this file. That is where the enemy pawns stand, and often the king. Sometimes this leads to an attack on two pieces at once. Nimzowitsch calls this a raid.

Start with lesson 11, where you put a rook on an open file. Lesson 37 shows the outpost, lesson 12 breaking into the seventh rank. In the games against Pritzel and Rabinowitsch both sides fight for the d-file.

Summarised by the editors in their own words. This is not a quotation.

Obstacles on the file

Often an enemy pawn is in the way. If it is protected by another pawn, it does little good to charge at it with many pieces. Nimzowitsch advises attacking it first with a pawn of your own. That way it loses its protection.

If only pieces protect the pawn, attack it with several pieces. Then you drive away its defenders, exchange them or shut them out until you have more attackers. Nimzowitsch calls this slow way evolutionary.

Only after that do you think of a sacrifice that clears the way by force. He calls this way revolutionary.

The outpost as a helper

If you cannot get any further on the file, an outpost often helps. That is a piece on the file in the enemy camp, protected by one of your own pawns. Usually it is a knight; on the edge files a, b, g and h it is more often a rook.

If your opponent wants to drive the outpost away, they often have to move a pawn. In doing so they weaken their position on the file. For Nimzowitsch, though, the outpost remains an aid; the real goal is the seventh rank.

A file alone is not enough

Nimzowitsch tells of a beginner who proudly showed off an open file. But he had already sacrificed his rook and queen. So a file is only useful to you if your major pieces can actually use it.

Sometimes a file serves only as a springboard. The rook moves forward a little and then switches to another file. Today, too, the open file is seen as an important goal for rooks. But only the concrete position shows whether it really achieves anything.

Where to find it in Nimzowitsch

• My System: I. Teil, 2. Kapitel - Die offene Turmlinie (original text)

  Overview of the chapter on the open file, with all its sections.

• My System: I. Teil, 2.1 Einleitung. Allgemeines und Definitionen original text not yet published

  Nimzowitsch calls the open file a pillar of his system and explains when a file is open.

• My System: I. Teil, 2.2 Die Entstehung (Geburt) der offenen Linie. Auf friedlichem Wege. Durch kriegerisches Vorgehen. Die Angriffsmarke (original text)

  How an open file comes about through an exchange or through a pawn advance against the point of attack.

• My System: I. Teil, 2.3 Das Ideal (Endzweck) jeder Linienoperation. Von kleinen Begleiterscheinungen. Raubzug, Umgebung original text not yet published

  The goal of every file is to break into the seventh or eighth rank, often with a raid or an outflanking move.

• My System: I. Teil, 2.4 Die möglichen Hindernisse auf dem Wege einer Operationslinie original text not yet published

  Protected and unprotected obstacles on the file and the slow or forcible attack against them.

• My System: I. Teil, 2.6 Der Vorposten. Der Angriffsradius. Das Märlein von der Zeitschrift. Womit besetzt man den Vorposten in einer Mittellinie und womit den in einer Randlinie? Der Rollentausch und was dieser beweise original text not yet published

  The outpost on the open file, its strength and the right piece for central and edge files.

In the course

• Clear paths for rooks
• A rook breaks in
• The outpost
• Nimzowitsch – Pritzel, Copenhagen 1922
• Rabinowitsch – Nimzowitsch, Baden-Baden 1925