ECO code: A00
Anderssen's Opening a5 begins with the moves 1. a3 a5. It is an uncommon and offbeat opening where both sides immediately push their rook pawns.
Characteristic: The move 1. a3 is somewhat waiting and aims to prevent ...Bb4 or prepare b4 later, but it does not contribute directly to central control or piece development. Black's reply 1...a5 similarly stakes space on the flank but does not challenge the center.
From an attacking or defensive perspective, both White and Black are playing somewhat non-committal, neither attacking nor defending the center actively at this early stage. Instead, these flank pawn moves are mostly about gaining space on the edges or preventing certain piece developments.
This opening does not attack the center directly. Both sides delay central pawn moves, so it often leads to a slow, maneuvering game rather than immediate central confrontation.
This opening is defined by the position shown on the board below. The moves displayed are a typical sequence that leads to it, but different sequences can reach the same position and still carry the same opening name.