Quick answer
Philidor Position is an endgame technique: Lucena bridge-building. Work from the first evidence position for Philidor Position, and begin by testing Ra8.
Begin from Ra8 in 2N4k/8/3K4/8/8/8/8/R6r w - - 3 3. Count the material, king routes, promotion squares and reserve tempi before applying a theoretical rule. The evidence answer is: Philidor Position: use the king's shelter and a checking-distance bridge before advancing the pawn. Candidate line: Ra8.
In the Philidor Position example, notice: side White; pieces White knight c8, Black king h8, White king d6, White rook a1, Black rook h1; legal first moves Ne7, Nb6, Na7, Kc7, Kd7, Ke7, Ke6, Ke5. This material report is evidence for the board shown here, not a checklist for every encounter with the idea.
Material and result question
The first evidence board tests Lucena bridge-building; the second board tests Lucena bridge-building. Board A’s recorded route is direct FEN setup. Board B’s recorded route is direct FEN setup. Use the Chess Wiki with the Endgames hub when a term needs a definition. Then compare Material Values with Lucena Position, Vancura Defense, Rook And Pawn On The Sixth Rank around the defender's only active counterplay.
The two inventories make the distinction concrete. A contains side White; pieces White knight c8, Black king h8, White king d6, White rook a1, Black rook h1; legal first moves Ne7, Nb6, Na7, Kc7, Kd7, Ke7, Ke6, Ke5; B contains side White; pieces Black king h8, White pawn c7, White king c6, Black rook h6, White rook c1; legal first moves Kb7, Kd7, Kd5, Kc5, Kb5. Compare the side to move before comparing the labels in the context of an outside passer used as a decoy.
Topic dossier for this page and board pair r1:2N4k | r2:8 | r3:3K4 | r4:8 | r5:8 | r6:8 | r7:8 | r8:R6r / r1:7k | r2:2P5 | r3:2K4r | r4:8 | r5:8 | r6:8 | r7:8 | r8:2R5: start with the defender's only active counterplay; then test an outside passer used as a decoy; keep the defender's fortress setup separate from the pawn's promotion square; use a reserve pawn move as the transfer check; and reserve the side-to-move tempo for the exception.
Conversion or defense plan
On the first board, calculate Ra8 after Ra8 and write down the opponent's best reply around the defender's only active counterplay. On the second board, calculate Kc5 after Kc5 and check an outside passer used as a decoy. Separate the practical conversion question from the result question; side to move and one checking distance can change the conclusion. In this case the useful condition is the side-to-move tempo.
Key claim: Philidor Position is illustrated here by Lucena bridge-building; the first concrete test is Ra8. The board anchor is 2N4k/8/3K4/8/8/8/8/R6r; the example is intentionally narrower than the topic label and should not be generalised without checking the surrounding position..
Practical boundary: To answer “What exact king, pawn, and move-order conditions decide philidor position, and how should each side play them?”, compare the recorded setup with Kc5 and the opponent's reply. The decision is useful only when the stated condition survives that concrete test on board 7k/2P5/2K4r/8/8/8/8/2R5. The evidence records No tablebase outcome is asserted by this generated record; verify the exact FEN before publication and the second board signature r1:7k | r2:2P5 | r3:2K4r | r4:8 | r5:8 | r6:8 | r7:8 | r8:2R5. The false-positive test is whether the defender's fortress setup appears without the pawn's promotion square, so the conclusion is useful only when the stated condition survives that concrete test.
Evidence positions
example-1: Lucena bridge-building
Show answer
Philidor Position: use the king's shelter and a checking-distance bridge before advancing the pawn. Candidate line: Ra8.
Why this position is here: Philidor Position is represented by Lucena bridge-building. This is a direct FEN setup with board anchor 2N4k/8/3K4/8/8/8/8/R6r; no opening history is inferred from the diagram.
FEN: 2N4k/8/3K4/8/8/8/8/R6r w - - 3 3
Question: What is the first concrete decision in this philidor position position?
Answer cue: Philidor Position: use the king's shelter and a checking-distance bridge before advancing the pawn. Candidate line: Ra8. The first candidate to test is Ra8. Replay Ra8 on board anchor 2N4k/8/3K4/8/8/8/8/R6r and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
example-2: Lucena bridge-building
Show answer
Philidor Position: use the king's shelter and a checking-distance bridge before advancing the pawn. Candidate line: Kc5.
Why this position is here: Philidor Position is represented by Lucena bridge-building. This is a direct FEN setup with board anchor 7k/2P5/2K4r/8/8/8/8/2R5; no opening history is inferred from the diagram.
FEN: 7k/2P5/2K4r/8/8/8/8/2R5 w - - 2 2
Question: What is the first concrete decision in this philidor position position?
Answer cue: Philidor Position: use the king's shelter and a checking-distance bridge before advancing the pawn. Candidate line: Kc5. The first candidate to test is Kc5. Replay Kc5 on board anchor 7k/2P5/2K4r/8/8/8/8/2R5 and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
example-3: Lucena bridge-building
Show answer
Philidor Position: use the king's shelter and a checking-distance bridge before advancing the pawn. Candidate line: Kh6.
Why this position is here: Philidor Position is represented by Lucena bridge-building. This is a direct FEN setup with board anchor 2R5/6kr/8/2K5/8/8/8/R7; no opening history is inferred from the diagram.
FEN: 2R5/6kr/8/2K5/8/8/8/R7 b - - 2 2
Question: What is the first concrete decision in this philidor position position?
Answer cue: Philidor Position: use the king's shelter and a checking-distance bridge before advancing the pawn. Candidate line: Kh6. The first candidate to test is Kh6. Replay Kh6 on board anchor 2R5/6kr/8/2K5/8/8/8/R7 and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
Reading the line
Read the first example (id example-1) as a complete record: continuation Ra8, source tablebase. This is a direct FEN setup with board anchor 2N4k/8/3K4/8/8/8/8/R6r; no opening history is inferred from the diagram. If A does not expose Lucena bridge-building, correct the evidence before relying on the prose.
Read the second example (id example-2) separately: continuation Kc5, source tablebase. Its feature is Lucena bridge-building; inventory side White; pieces Black king h8, White pawn c7, White king c6, Black rook h6, White rook c1; legal first moves Kb7, Kd7, Kd5, Kc5, Kb5. Compare what changes between Ra8 and Kc5.
Boundary cases
The main mistake to avoid with Philidor Position is applying a remembered endgame rule while ignoring side to move, king placement or an unverified result. In A, the missing condition must be located in r1:2N4k | r2:8 | r3:3K4 | r4:8 | r5:8 | r6:8 | r7:8 | r8:R6r after Ra8; in B, test it against r1:7k | r2:2P5 | r3:2K4r | r4:8 | r5:8 | r6:8 | r7:8 | r8:2R5 after Kc5.
For Philidor Position, the first board's evidence boundary (after Ra8) is No tablebase outcome is asserted by this generated record; verify the exact FEN before publication. The second board's evidence boundary for Philidor Position is No tablebase outcome is asserted by this generated record; verify the exact FEN before publication. If a trusted source or careful calculation changes the conclusion around a reserve pawn move, update both the evidence record and this article.
Practice from a real game
play the position for both sides, record the critical tempo, and verify the exact FEN against the cited tablebase before publication. Start with A's side to move and r1:2N4k | r2:8 | r3:3K4 | r4:8 | r5:8 | r6:8 | r7:8 | r8:R6r; record two candidates, the reply to Ra8 and the correction. Repeat with B's side to move and r1:7k | r2:2P5 | r3:2K4r | r4:8 | r5:8 | r6:8 | r7:8 | r8:2R5; the changed board tests transfer rather than diagram memory.
After the drill, compare your notes with Lucena Position, Vancura Defense, Rook And Pawn On The Sixth Rank through the pawn's promotion square. Keep A's rejected alternative beside B's chosen line Kc5; this shows whether the conclusion survived a new board signature.
Sources and scope
Sources for Philidor Position: Syzygy tablebase verification reference, 1chess.online editorial scope. Source ids are tablebase, original-analysis. Primary evidence hook: tablebase. Comparisons and practice notes are editorial. Evidence revision: 2026-08-remediation-r2.
Scope note for board pair r1:2N4k | r2:8 | r3:3K4 | r4:8 | r5:8 | r6:8 | r7:8 | r8:R6r / r1:7k | r2:2P5 | r3:2K4r | r4:8 | r5:8 | r6:8 | r7:8 | r8:2R5: this page does not claim that Ra8 is an engine principal variation, that an exact endgame result is verified when the evidence says it is not, or that a tool output replaces human calculation. The conclusion is limited to the recorded boundary and the exception the defender's fortress setup.