Ruy Lopez: Berlin Without the Wall

Ever since Vladimir Kramnik used the Berlin Defense against Garry Kasparov, players of the white pieces have been struggling to exploit their perceived advantage. The success of Black in defending and even winning at times, has led to the variation being called the Berlin Wall. That variation uses 4.0-0 Nxe4 which often leads to a trade of queens with White having the advantages of space and pawn structure. The opening code for this line is covered under C67. The Berlin line with 4.0-0 d6 is covered under C66. Another and different example of the Berlin from C65 is shown below. C65 considers 4.0-0 and other moves. After 4.0-0 Bc5 we have a Berlin Classical in which the queens are retained and play is open.