Van’t Kruijs Opening 1. e3 (A00)
The Van't Kruijs Opening is a chess opening defined by the move:
It is named after the Amsterdam player Maarten van't Kruijs (1813–85) who won the sixth Dutch championship in 1878. As this opening move is rarely played, it is considered an irregular opening, and thus it is classified under the A00 code in the Encyclopaedia of Chess Openings (ECO).
The opening 1.e3 is not popular according to ChessBase: it ranks eleventh in popularity out of the twenty possible first moves. It releases the king's bishop, and makes a modest claim of the centre, but the move is somewhat passive. The queen's bishop's development is somewhat hindered by the pawn on e3, and White usually wants to take more than a modest stake of the centre.
Although not very aggressive for a first move, play may transpose to lines of the English Opening (c2–c4), Queen's Pawn Game (d2–d4), or reversed French Defence (delayed d2–d4) or reversed Dutch Defence (f2–f4) positions.
The Van't Kruijs Opening is not a common choice for grandmasters, but its ability to transpose into many different openings explains its attraction for some people such as the Czech grandmaster Pavel Blatny, Aron Nimzowitsch and Bent Larsen. Garry Kasparov has used the move against the Fritz chess engine to get it "out of book".