The eastern section of the Kremlin's protective wall running along Red Square had the following special feature from the start: Was the Kremlin from its southern side not only through the wall, but also through the Moskva River and from the west or northwest through the (today Neglinnaja that only flows undergroundShielded from the outside world, its wall in the area of its eastern section facing Kitai-Gorod was not additionally protected by natural obstacles. Since the fortress was therefore considered to be particularly endangered from its eastern side, the wall in this area is particularly high at up to 19 meters. In order to further increase the Kremlin's ability to defend itself against frequent attacks, an artificial moat about 30 meters wide and about 12 to 13 meters deep was created along its eastern wall at the beginning of the 16th century. This as Alewis-Graben ( Алевизов ров , after its builder Alewis the newnamed) connecting trench between the Neglinnaja and the Moskva existed until the beginning of the 19th century, when it was no longer found necessary and was filled in. Of the three Kremlin towers on Red Square, two have entrance gates, to which bridges previously built for this purpose led across the Alewis moat. Today nothing on the eastern Kremlin wall reminds of the moat and these bridges.