How many moves does it take a soldier to cross the river?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws for movement, checkmate and both repetition rulings: a side that forces a repetition by perpetual check or perpetual chase loses rather than drawing. The chase half has not been validated against the official casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it before publishing.
Direct answer
Two moves. Soldiers start on their side's fourth rank. The first step forward puts a soldier on the river bank, still on its own side, and the second takes it across. Only after that second step may it also move sideways.
Where 'crossed' begins
Counting from your own back rank: the chariots, horses, elephants, advisors and general are on the first rank, the cannons on the third, the soldiers on the fourth. The fifth rank is your river bank. The river is a gap, not a rank, so the next point forward is the sixth rank, on the opponent's side. A soldier on your own river bank has not crossed, and it still moves only forward.
Why this matters in the opening
A soldier advanced one step, as in the Pawn Opening's 兵七進一 (P7+1), stands on its own river bank. It has not crossed and cannot yet move sideways; one more step takes it over, where it can be attacked by the enemy soldier on the same file. That is why the first push is as much about freeing space for the horse behind it as about marching forward. See the Pawn Opening.
What crossing gives it
Once across, the soldier moves one point forward or one point to either side, still never backwards. Its value roughly doubles because it now attacks up to three points instead of one; see what a crossed soldier is worth.
Related questions
Can a soldier move sideways on its own river bank?
No. The river bank is still your own half. Sideways moves start only once it stands on the far side.
Does crossing the river count as moving two points?
No. Crossing is one ordinary step, because there are no points inside the river.
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