This complex is made up of the Palace of Contreras, or Polentinos, as the main construction and a number of buildings that have been added over the years (since the installation of the Military Academy in 1875 to when it became a Military History Archive in 1993).
It dates from the beginning of the 16th century and is made of granite ashlar work and masonry. The porch is decorated in Plateresque style with military motifs and the courtyard lintels are decorated with medallions.
The Palace is set around a quadrangular central courtyard surrounded by galleries and each front has five columns, with monolithic shafts, Doric capitals and bases. The first-floor gallery is made up of shorter columns which also support sculpted lintels and coats of arms. The tributes room is of particular interest, with an important coffered ceiling made of wooden coffers and beams set on carved corbels.
Today it is used as the Military History Archive and Army Museum.