How many moves does it typically take a cannon to reach the enemy palace?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
Often just one or two moves. Because the starting position already gives both cannons a clear line across the whole board, a single traverse, 炮二平五, puts a cannon on the central file aimed straight at the enemy palace from the very first move. Few other pieces can create a genuine threat that quickly.
Why the cannon is the fastest piece to threaten something
A chariot needs a file opened first; a horse needs several moves to cross the board even without obstruction. The cannon's starting line is already open, so its speed advantage is built into the setup rather than earned through play, which is exactly why a cannon move is so often the very first move of a game.
Speed is not the same as follow-up
Arriving fast only matters if a second attacker can arrive in time to support it. A cannon alone on the central file is pressure, not a winning attack, see how to attack the palace for what actually needs to follow it.
Related questions
Is the cannon always the fastest piece to get involved?
Usually, yes, though a horse defending the central soldier is close behind it in typical openings.
Does a second cannon arrive just as quickly?
Not usually, see the fastest way to activate a cannon for why the second one should generally wait.
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