The Master of the Knights Templar's great seal was double-sided and showed the picture of The Dome of the Rock (some opinions are that the picture represents a circular dome of the Church of the Holy Sepulchre) on one side and the Order's symbol of two knights on one horse on the other side. There was also a smaller, single-sided seal, which showed the Dome of the Rock (or the circular dome of the Holy Sepulchre). Every Grand Master seal shares distinctive characteristics. In order to avoid misuse, special measures were taken regarding the seals. They were kept in a locked compartment which required three keys to open. The Grand Master himself kept one of these keys, and two of his high officials held the others. The forgery of the seals was a very difficult process because each seal was u